Posted by Aden Haussmann, Associate Product Manager and Sumeet Sharma, Play Partnerships Trust & Safety Lead

Android uses the best of Google AI and our advanced security expertise to tackle mobile scams from every angle. Over the last few years, we’ve launched industry-leading features to detect scams and protect users across phone calls, text messages and messaging app chat notifications.

These efforts are making a real difference in the lives of Android users. According to a recent YouGov survey¹ commissioned by Google, Android users were 58% more likely than iOS users to report they had not received any scam texts in the prior week².

But our work doesn’t stop there. Scammers are continuously evolving, using more sophisticated social engineering tactics to trick users into sharing their phone screen while on the phone to visit malicious websites, reveal sensitive information, send funds or download harmful apps. One popular scam involves criminals impersonating banks or other trusted institutions on the phone to try to manipulate victims into sharing their screen in order to reveal banking information or make a financial transfer.

To help combat these types of financial scams, we launched a pilot earlier this year in the UK focused on in-call protections for financial apps.

How the in-call scam protection works on Android

When you launch a participating financial app while screen sharing and on a phone call with a number that is not saved in your contacts, your Android device³ will automatically warn you about the potential dangers and give you the option to end the call and to stop screen sharing with just one tap. The warning includes a 30-second pause period before you’re able to continue, which helps break the ‘spell’ of the scammer's social engineering, disrupting the false sense of urgency and panic commonly used to manipulate you into a scam.

Bringing in-call scam protections to more users on Android

The UK pilot of Android’s in-call scam protections has already helped thousands of users end calls that could have cost them a significant amount of money. Following this success, and alongside recently launched pilots with financial apps in Brazil and India, we’ve now expanded this protection to most major UK banks.

We’ve also started to pilot this protection with more app types, including peer-to-peer (P2P) payment apps. Today, we’re taking the next step in our expansion by rolling out a pilot of this protection in the United States⁴ with a number of popular fintechs like Cash App and banks, including JPMorganChase.

We are committed to collaborating across the ecosystem to help keep people safe from scams. We look forward to learning from these pilots and bringing these critical safeguards to even more users in the future.

Notes

Posted by Dave Kleidermacher, VP, Platforms Security & Privacy, Google

Technology should bring people closer together, not create walls. Being able to communicate and connect with friends and family should be easy regardless of the phone they use. That’s why Android has been building experiences that help you stay connected across platforms.

As part of our efforts to continue to make cross-platform communication more seamless for users, we've made Quick Share interoperable with AirDrop, allowing for two-way file sharing between Android and iOS devices, starting with the Pixel 10 Family. This new feature makes it possible to quickly share your photos, videos, and files with people you choose to communicate with, without worrying about the kind of phone they use.

Most importantly, when you share personal files and content, you need to trust that it stays secure. You can share across devices with confidence knowing we built this feature with security at its core, protecting your data with strong safeguards that have been tested by independent security experts.

Secure by Design

We built Quick Share’s interoperability support for AirDrop with the same rigorous security standards that we apply to all Google products. Our approach to security is proactive and deeply integrated into every stage of the development process. This includes:

• Threat Modeling: We identify and address potential security risks before they can become a problem.
• Internal Security Design and Privacy Reviews: Our dedicated security and privacy teams thoroughly review the design to ensure it meets our high standards.
• Internal Penetration Testing: We conduct extensive in-house testing to identify and fix vulnerabilities.

This Secure by Design philosophy ensures that all of our products are not just functional but also fundamentally secure.

This feature is also protected by a multi-layered security approach to ensure a safe sharing experience from end-to-end, regardless of what platform you’re on.

• Secure Sharing Channel: The communication channel itself is hardened by our use of Rust to develop this feature. This memory-safe language is the industry benchmark for building secure systems and provides confidence that the connection is protected against buffer overflow attacks and other common vulnerabilities.
• Built-in Platform Protections: This feature is strengthened by the robust built-in security of both Android and iOS. On Android, security is built in at every layer. Our deep investment in Rust at the OS level hardens the foundation, while proactive defenses like Google Play Protect work to keep your device safe. This is complemented by the security architecture of iOS that provides its own strong safeguards that mitigate malicious files and exploitation. These overlapping protections on both platforms work in concert with the secure connection to provide comprehensive safety for your data when you share or receive.
• You’re in Control: Sharing across platforms works just like you're used to: a file requires your approval before being received, so you're in control of what you accept.

The Power of Rust: A Foundation of Secure Communication

A key element of our security strategy for the interoperability layer between Quick Share and AirDrop is the use of the memory-safe Rust programming language. Recognized by security agencies around the world, including the NSA and CISA, Rust is widely considered the industry benchmark for building secure systems because it eliminates entire classes of memory-safety vulnerabilities by design.

Rust is already a cornerstone of our broader initiative to eliminate memory safety bugs across Android. Its selection for this feature was deliberate, driven by the unique security challenges of cross-platform communication that demanded the most robust protections for memory safety.

The core of this feature involves receiving and parsing data sent over a wireless protocol from another device. Historically, when using a memory-unsafe language, bugs in data parsing logic are one of the most common sources of high-severity security vulnerabilities. A malformed data packet sent to a parser written in a memory-unsafe language can lead to buffer overflows and other memory corruption bugs, creating an opportunity for code execution.

This is precisely where Rust provides a robust defense. Its compiler enforces strict ownership and borrowing rules at compile time, which guarantees memory safety. Rust removes entire classes of memory-related bugs. This means our implementation is inherently resilient against attackers attempting to use maliciously crafted data packets to exploit memory errors.

Secure Sharing Using AirDrop's "Everyone" Mode

To ensure a seamless experience for both Android and iOS users, Quick Share currently works with AirDrop's "Everyone for 10 minutes" mode. This feature does not use a workaround; the connection is direct and peer-to-peer, meaning your data is never routed through a server, shared content is never logged, and no extra data is shared. As with "Everyone for 10 minutes" mode on any device when you’re sharing between non-contacts, you can ensure you're sharing with the right person by confirming their device name on your screen with them in person.

This implementation using "Everyone for 10 minutes” mode is just the first step in seamless cross-platform sharing, and we welcome the opportunity to work with Apple to enable “Contacts Only” mode in the future.

Tested by Independent Security Experts

After conducting our own secure product development, internal threat modeling, privacy reviews, and red team penetration tests, we engaged with NetSPI, a leading third-party penetration testing firm, to further validate the security of this feature and conduct an independent security assessment. The assessment found the interoperability between Quick Share and AirDrop is secure, is “notably stronger” than other industry implementations and does not leak any information.

Based on these internal and external assessments, we believe our implementation provides a strong security foundation for cross-platform file sharing for both Android and iOS users. We will continue to evaluate and enhance the implementation’s security in collaboration with additional third-party partners.

To complement this deep technical audit, we also sought expert third-party perspective on our approach from Dan Boneh, a renowned security expert and professor at Stanford University:

“Google’s work on this feature, including the use of memory safe Rust for the core communications layer, is a strong example of how to build secure interoperability, ensuring that cross-platform information sharing remains safe. I applaud the effort to open more secure information sharing between platforms and encourage Google and Apple to work together more on this."

The Future of File-Sharing Should Be Interoperable

This is just the first step as we work to improve the experience and expand it to more devices. We look forward to continuing to work with industry partners to make connecting and communicating across platforms a secure, seamless experience for all users.

Posted by Jeff Vander Stoep, Android

Last year, we wrote about why a memory safety strategy that focuses on vulnerability prevention in new code quickly yields durable and compounding gains. This year we look at how this approach isn’t just fixing things, but helping us move faster.

The 2025 data continues to validate the approach, with memory safety vulnerabilities falling below 20% of total vulnerabilities for the first time.

Updated data for 2025. This data covers first-party and third-party (open source) code changes to the Android platform across C, C++, Java, Kotlin, and Rust. This post is published a couple of months before the end of 2025, but Android’s industry-standard 90-day patch window means that these results are very likely close to final. We can and will accelerate patching when necessary.

We adopted Rust for its security and are seeing a 1000x reduction in memory safety vulnerability density compared to Android’s C and C++ code. But the biggest surprise was Rust's impact on software delivery. With Rust changes having a 4x lower rollback rate and spending 25% less time in code review, the safer path is now also the faster one.

In this post, we dig into the data behind this shift and also cover:

• How we’re expanding our reach: We're pushing to make secure code the default across our entire software stack. We have updates on Rust adoption in first-party apps, the Linux kernel, and firmware.
• Our first rust memory safety vulnerability...almost: We'll analyze a near-miss memory safety bug in unsafe Rust: how it happened, how it was mitigated, and steps we're taking to prevent recurrence. It’s also a good chance to answer the question “if Rust can have memory safety issues, why bother at all?”

Building Better Software, Faster

Developing an operating system requires the low-level control and predictability of systems programming languages like C, C++, and Rust. While Java and Kotlin are important for Android platform development, their role is complementary to the systems languages rather than interchangeable. We introduced Rust into Android as a direct alternative to C and C++, offering a similar level of control but without many of their risks. We focus this analysis on new and actively developed code because our data shows this to be an effective approach.

When we look at development in systems languages (excluding Java and Kotlin), two trends emerge: a steep rise in Rust usage and a slower but steady decline in new C++.

Net lines of code added: Rust vs. C++, first-party Android code.
This chart focuses on first-party (Google-developed) code (unlike the previous chart that included all first-party and third-party code in Android.) We only include systems languages, C/C++ (which is primarily C++), and Rust.

The chart shows that the volume of new Rust code now rivals that of C++, enabling reliable comparisons of software development process metrics. To measure this, we use the DORA¹ framework, a decade-long research program that has become the industry standard for evaluating software engineering team performance. DORA metrics focus on:

• Throughput: the velocity of delivering software changes.
• Stability: the quality of those changes.

Cross-language comparisons can be challenging. We use several techniques to ensure the comparisons are reliable.

• Similar sized changes: Rust and C++ have similar functionality density, though Rust is slightly denser. This difference favors C++, but the comparison is still valid. We use Gerrit’s change size definitions.
• Similar developer pools: We only consider first-party changes from Android platform developers. Most are software engineers at Google, and there is considerable overlap between pools with many contributing in both.
• Track trends over time: As Rust adoption increases, are metrics changing steadily, accelerating the pace, or reverting to the mean?

Throughput

Code review is a time-consuming and high-latency part of the development process. Reworking code is a primary source of these costly delays. Data shows that Rust code requires fewer revisions. This trend has been consistent since 2023. Rust changes of a similar size need about 20% fewer revisions than their C++ counterparts.

In addition, Rust changes currently spend about 25% less time in code review compared to C++. We speculate that the significant change in favor of Rust between 2023 and 2024 is due to increased Rust expertise on the Android team.

While less rework and faster code reviews offer modest productivity gains, the most significant improvements are in the stability and quality of the changes.

Stability

Stable and high-quality changes differentiate Rust. DORA uses rollback rate for evaluating change stability. Rust's rollback rate is very low and continues to decrease, even as its adoption in Android surpasses C++.

For medium and large changes, the rollback rate of Rust changes in Android is ~4x lower than C++. This low rollback rate doesn't just indicate stability; it actively improves overall development throughput. Rollbacks are highly disruptive to productivity, introducing organizational friction and mobilizing resources far beyond the developer who submitted the faulty change. Rollbacks necessitate rework and more code reviews, can also lead to build respins, postmortems, and blockage of other teams. Resulting postmortems often introduce new safeguards that add even more development overhead.

In a self-reported survey from 2022, Google software engineers reported that Rust is both easier to review and more likely to be correct. The hard data on rollback rates and review times validates those impressions.

Putting it all together

Historically, security improvements often came at a cost. More security meant more process, slower performance, or delayed features, forcing trade-offs between security and other product goals. The shift to Rust is different: we are significantly improving security and key development efficiency and product stability metrics.

Expanding Our Reach

With Rust support now mature for building Android system services and libraries, we are focused on bringing its security and productivity advantages elsewhere.

• Kernel: Android’s 6.12 Linux kernel is our first kernel with Rust support enabled and our first production Rust driver. More exciting projects are underway, such as our ongoing collaboration with Arm and Collabora on a Rust-based kernel-mode GPU driver.
• Firmware: The combination of high privilege, performance constraints, and limited applicability of many security measures makes firmware both high-risk, and challenging to secure. Moving firmware to Rust can yield a major improvement in security. We have been deploying Rust in firmware for years now, and even released tutorials, training, and code for the wider community. We’re particularly excited about our collaboration with Arm on Rusted Firmware-A.
• First-party applications: Rust is ensuring memory safety from the ground up in several security-critical Google applications, such as:
• Nearby Presence: The protocol for securely and privately discovering local devices over Bluetooth is implemented in Rust and is currently running in Google Play Services.
• MLS: The protocol for secure RCS messaging is implemented in Rust and will be included in the Google Messages app in a future release.
• Chromium: Parsers for PNG, JSON, and web fonts have been replaced with memory-safe implementations in Rust, making it easier for Chromium engineers to deal with data from the web while following the Rule of 2.

These examples highlight Rust's role in reducing security risks, but memory-safe languages are only one part of a comprehensive memory safety strategy. We continue to employ a defense-in-depth approach, the value of which was clearly demonstrated in a recent near-miss.

Our First Rust Memory Safety Vulnerability...Almost

We recently avoided shipping our very first Rust-based memory safety vulnerability: a linear buffer overflow in CrabbyAVIF. It was a near-miss. To ensure the patch received high priority and was tracked through release channels, we assigned it the identifier CVE-2025-48530. While it’s great that the vulnerability never made it into a public release, the near-miss offers valuable lessons. The following sections highlight key takeaways from our postmortem.

Scudo Hardened Allocator for the Win

A key finding is that Android’s Scudo hardened allocator deterministically rendered this vulnerability non-exploitable due to guard pages surrounding secondary allocations. While Scudo is Android’s default allocator, used on Google Pixel and many other devices, we continue to work with partners to make it mandatory. In the meantime, we will issue CVEs of sufficient severity for vulnerabilities that could be prevented by Scudo.

In addition to protecting against overflows, Scudo’s use of guard pages helped identify this issue by changing an overflow from silent memory corruption into a noisy crash. However, we did discover a gap in our crash reporting: it failed to clearly show that the crash was a result of an overflow, which slowed down triage and response. This has been fixed, and we now have a clear signal when overflows occur into Scudo guard pages.

Unsafe Review and Training

Operating system development requires unsafe code, typically C, C++, or unsafe Rust (for example, for FFI and interacting with hardware), so simply banning unsafe code is not workable. When developers must use unsafe, they should understand how to do so soundly and responsibly

To that end, we are adding a new deep dive on unsafe code to our Comprehensive Rust training. This new module, currently in development, aims to teach developers how to reason about unsafe Rust code, soundness and undefined behavior, as well as best practices like safety comments and encapsulating unsafe code in safe abstractions.

Better understanding of unsafe Rust will lead to even higher quality and more secure code across the open source software ecosystem and within Android. As we'll discuss in the next section, our unsafe Rust is already really quite safe. It’s exciting to consider just how high the bar can go.

Comparing Vulnerability Densities

This near-miss inevitably raises the question: "If Rust can have memory safety vulnerabilities, then what’s the point?"

The point is that the density is drastically lower. So much lower that it represents a major shift in security posture. Based on our near-miss, we can make a conservative estimate. With roughly 5 million lines of Rust in the Android platform and one potential memory safety vulnerability found (and fixed pre-release), our estimated vulnerability density for Rust is 0.2 vuln per 1 million lines (MLOC).

Our historical data for C and C++ shows a density of closer to 1,000 memory safety vulnerabilities per MLOC. Our Rust code is currently tracking at a density orders of magnitude lower: a more than 1000x reduction.

Memory safety rightfully receives significant focus because the vulnerability class is uniquely powerful and (historically) highly prevalent. High vulnerability density undermines otherwise solid security design because these flaws can be chained to bypass defenses, including those specifically targeting memory safety exploits. Significantly lowering vulnerability density does not just reduce the number of bugs; it dramatically boosts the effectiveness of our entire security architecture.

The primary security concern regarding Rust generally centers on the approximately 4% of code written within unsafe{} blocks. This subset of Rust has fueled significant speculation, misconceptions, and even theories that unsafe Rust might be more buggy than C. Empirical evidence shows this to be quite wrong.

Our data indicates that even a more conservative assumption, that a line of unsafe Rust is as likely to have a bug as a line of C or C++, significantly overestimates the risk of unsafe Rust. We don’t know for sure why this is the case, but there are likely several contributing factors:

• unsafe{} doesn't actually disable all or even most of Rust’s safety checks (a common misconception).
• The practice of encapsulation enables local reasoning about safety invariants.
• The additional scrutiny that unsafe{} blocks receive.

Final Thoughts

Historically, we had to accept a trade-off: mitigating the risks of memory safety defects required substantial investments in static analysis, runtime mitigations, sandboxing, and reactive patching. This approach attempted to move fast and then pick up the pieces afterwards. These layered protections were essential, but they came at a high cost to performance and developer productivity, while still providing insufficient assurance.

While C and C++ will persist, and both software and hardware safety mechanisms remain critical for layered defense, the transition to Rust is a different approach where the more secure path is also demonstrably more efficient. Instead of moving fast and then later fixing the mess, we can move faster while fixing things. And who knows, as our code gets increasingly safe, perhaps we can start to reclaim even more of that performance and productivity that we exchanged for security, all while also improving security.

Acknowledgments

Thank you to the following individuals for their contributions to this post:

• Ivan Lozano for compiling the detailed postmortem on CVE-2025-48530.
• Chris Ferris for validating the postmortem’s findings and improving Scudo’s crash handling as a result.
• Dmytro Hrybenko for leading the effort to develop training for unsafe Rust and for providing extensive feedback on this post.
• Alex Rebert and Lars Bergstrom for their valuable suggestions and extensive feedback on this post.
• Peter Slatala, Matthew Riley, and Marshall Pierce for providing information on some of the places where Rust is being used in Google's apps.

Finally, a tremendous thank you to the Android Rust team, and the entire Android organization for your relentless commitment to engineering excellence and continuous improvement.

Notes

Posted by Lyubov Farafonova, Product Manager, Phone by Google; Alberto Pastor Nieto, Sr. Product Manager Google Messages and RCS Spam and Abuse; Vijay Pareek, Manager, Android Messaging Trust and Safety As Cybersecurity Awareness Month wraps up, we’re focusing on one of today's most pervasive digital threats: mobile scams. In the last 12 months, fraudsters have used advanced AI tools to create more convincing schemes, resulting in over $400 billion in stolen funds globally.¹

For years, Android has been on the frontlines in the battle against scammers, using the best of Google AI to build proactive, multi-layered protections that can anticipate and block scams before they reach you. Android’s scam defenses protect users around the world from over 10 billion suspected malicious calls and messages every month². In addition, Google continuously performs safety checks to maintain the integrity of the RCS service. In the past month alone, this ongoing process blocked over 100 million suspicious numbers from using RCS, stopping potential scams before they could even be sent.

To show how our scam protections work in the real world, we asked users and independent security experts to compare how well Android and iOS protect you from these threats. We're also releasing a new report that explains how modern text scams are orchestrated, helping you understand the tactics fraudsters use and how to spot them.

Survey shows Android users’ confidence in scam protections

Google and YouGov³ surveyed 5,000 smartphone users across the U.S., India, and Brazil about their scam experiences. The findings were clear: Android users reported receiving fewer scam texts and felt more confident that their device was keeping them safe.

• Android users were 58% more likely than iOS users to say they had not received any scam texts in the week prior to the survey. The advantage was even stronger on Pixel, where users were 96% more likely than iPhone owners to report zero scam texts⁴.
• At the other end of the spectrum, iOS users were 65% more likely than Android users to report receiving three or more scam texts in a week. The difference became even more pronounced when comparing iPhone to Pixel, with iPhone users 136% more likely to say they had received a heavy volume of scam messages⁴.
• Android users were 20% more likely than iOS users to describe their device’s scam protections as “very effective” or “extremely effective.” When comparing Pixel to iPhone, iPhone users were 150% more likely to say their device was not effective at all in stopping mobile fraud.

YouGov study findings on users’ experience with scams on Android and iOS

Security researchers and analysts highlight Android’s AI-driven safeguards against sophisticated scams

In a recent evaluation by Counterpoint Research⁵, a global technology market research firm, Android smartphones were found to have the most AI-powered protections. The independent study compared the latest Pixel, Samsung, Motorola, and iPhone devices, and found that Android provides comprehensive AI-driven safeguards across ten key protection areas, including email protections, browsing protections, and on-device behavioral protections. By contrast, iOS offered AI-powered protections in only two categories. You can see the full comparison in the visual below.

Counterpoint Research comparison of Android and iOS AI-powered protections

Cybersecurity firm Leviathan Security Group conducted a funded evaluation⁶ of scam and fraud protection on the iPhone 17, Moto Razr+ 2025, Pixel 10 Pro, and Samsung Galaxy Z Fold 7. Their analysis found that Android smartphones, led by the Pixel 10 Pro, provide the highest level of default scam and fraud protection.The report particularly noted Android's robust call screening, scam detection, and real-time scam warning authentication capabilities as key differentiators. Taken together, these independent expert assessments conclude that Android’s AI-driven safeguards provide more comprehensive and intelligent protection against mobile scams.

Leviathan Security Group comparison of scam protections across various devices

Why Android users see fewer scams

Android’s proactive protections work across the platform to help you stay ahead of threats with the best of Google AI.

Here’s how they work:

• Keeping your messages safe: Google Messages automatically filters known spam by analyzing sender reputation and message content, moving suspicious texts directly to your "spam & blocked" folder to keep them out of sight. For more complex threats, Scam Detection uses on-device AI to analyze messages from unknown senders for patterns of conversational scams (like pig butchering) and provide real-time warnings⁶. This helps secure your privacy while providing a robust shield against text scams. As an extra safeguard, Google Messages also helps block suspicious links in messages that are determined to be spam or scams.
• Combatting phone call scams: Phone by Google automatically blocks known spam calls so your phone never even rings, while Call Screen⁵ can answer the call on your behalf to identify fraudsters. If you answer, the protection continues with Scam Detection, which uses on-device AI to provide real-time warnings for suspicious conversational patterns⁶. This processing is completely ephemeral, meaning no call content is ever saved or leaves your device. Android also helps stop social engineering during the call itself by blocking high-risk actions⁷ like installing untrusted apps or disabling security settings, and warns you if your screen is being shared unknowingly.

These safeguards are built directly into the core of Android, alongside other features like real-time app scanning in Google Play Protect and enhanced Safe Browsing in Chrome using LLMs. With Android, you can trust that you have intelligent, multi-layered protection against scams working for you.

Android is always evolving to keep you one step ahead of scams

In a world of evolving digital threats, you deserve to feel confident that your phone is keeping you safe. That’s why we use the best of Google AI to build intelligent protections that are always improving and work for you around the clock, so you can connect, browse, and communicate with peace of mind.

See these protections in action in our new infographic and learn more about phone call scams in our 2025 Phone by Google Scam Report.

---

1: Data from Global Anti-Scam Alliance, October 2025 ↩

2: This total comprises all instances where a message or call was proactively blocked or where a user was alerted to potential spam or scam activity. ↩

3: Google/YouGov survey, July-August, n=5,100 (1,700 each in the US, Brazil and India), with adults who use their smartphones daily and who have been exposed to a scam or fraud attempt on their smartphone. Survey data have been weighted to smartphone population adults in each country. ↩

4: Among users who use the default texting app on their smartphone ↩

5: Google/Counterpoint Research, “Assessing the State of AI-Powered Mobile Security”, Oct. 2025; based on comparing the Pixel 10 Pro, iPhone 17 Pro, Samsung Galaxy S25 Ultra, OnePlus 13, Motorola Razr+ 2025. Evaluation based on no-cost smartphone features enabled by default. Some features may not be available in all countries. ↩

6: Google/Leviathan Security Group, “October 2025 Mobile Platform Security & Fraud Prevention Assessment”, Oct. 2025; based on comparing the Pixel 10 Pro, iPhone 17 Pro, Samsung Galaxy Z Fold 7 and Motorola Razr+ 2025. Evaluation based on no-cost smartphone features enabled by default. Some features may not be available in all countries. ↩ ↩

7: Accuracy may vary. Availability varies. ↩ ↩ ↩

One year from now, with the release of Chrome 154 in October 2026, we will change the default settings of Chrome to enable “Always Use Secure Connections”. This means Chrome will ask for the user's permission before the first access to any public site without HTTPS.

The “Always Use Secure Connections” setting warns users before accessing a site without HTTPS

Chrome Security's mission is to make it safe to click on links. Part of being safe means ensuring that when a user types a URL or clicks on a link, the browser ends up where the user intended. When links don't use HTTPS, an attacker can hijack the navigation and force Chrome users to load arbitrary, attacker-controlled resources, and expose the user to malware, targeted exploitation, or social engineering attacks. Attacks like this are not hypothetical—software to hijack navigations is readily available and attackers have previously used insecure HTTP to compromise user devices in a targeted attack.

Since attackers only need a single insecure navigation, they don't need to worry that many sites have adopted HTTPS—any single HTTP navigation may offer a foothold. What's worse, many plaintext HTTP connections today are entirely invisible to users, as HTTP sites may immediately redirect to HTTPS sites. That gives users no opportunity to see Chrome's "Not Secure" URL bar warnings after the risk has occurred, and no opportunity to keep themselves safe in the first place.

To address this risk, we launched the “Always Use Secure Connections” setting in 2022 as an opt-in option. In this mode, Chrome attempts every connection over HTTPS, and shows a bypassable warning to the user if HTTPS is unavailable. We also previously discussed our intent to move towards HTTPS by default. We now think the time has come to enable “Always Use Secure Connections” for all users by default.

Now is the time.

For more than a decade, Google has published the HTTPS transparency report, which tracks the percentage of navigations in Chrome that use HTTPS. For the first several years of the report, numbers saw an impressive climb, starting at around 30-45% in 2015, and ending up around the 95-99% range around 2020. Since then, progress has largely plateaued.

HTTPS adoption expressed as a percentage of main frame page loads

This rise represents a tremendous improvement to the security of the web, and demonstrates that HTTPS is now mature and widespread. This level of adoption is what makes it possible to consider stronger mitigations against the remaining insecure HTTP.

Balancing user safety with friction

While it may at first seem that 95% HTTPS means that the problem is mostly solved, the truth is that a few percentage points of HTTP navigations is still a lot of navigations. Since HTTP navigations remain a regular occurrence for most Chrome users, a naive approach to warning on all HTTP navigations would be quite disruptive. At the same time, as the plateau demonstrates, doing nothing would allow this risk to persist indefinitely. To balance these risks, we have taken steps to ensure that we can help the web move towards safer defaults, while limiting the potential annoyance warnings will cause to users.

One way we're balancing risks to users is by making sure Chrome does not warn about the same sites excessively. In all variants of the "Always Use Secure Connections" settings, so long as the user regularly visits an insecure site, Chrome will not warn the user about that site repeatedly. This means that rather than warn users about 1 out of 50 navigations, Chrome will only warn users when they visit a new (or not recently visited) site without using HTTPS.

To further address the issue, it's important to understand what sort of traffic is still using HTTP. The largest contributor to insecure HTTP by far, and the largest contributor to variation across platforms, is insecure navigations to private sites. The graph above includes both those to public sites, such as example.com, and navigations to private sites, such as local IP addresses like 192.168.0.1, single-label hostnames, and shortlinks like intranet/. While it is free and easy to get an HTTPS certificate that is trusted by Chrome for a public site, acquiring an HTTPS certificate for a private site unfortunately remains complicated. This is because private names are "non-unique"—private names can refer to different hosts on different networks. There is no single owner of 192.168.0.1 for a certification authority to validate and issue a certificate to.

HTTP navigations to private sites can still be risky, but are typically less dangerous than their public site counterparts because there are fewer ways for an attacker to take advantage of these HTTP navigations. HTTP on private sites can only be abused by an attacker also on your local network, like on your home wifi or in a corporate network.

If you exclude navigations to private sites, then the distribution becomes much tighter across platforms. In particular, Linux jumps from 84% HTTPS to nearly 97% HTTPS when limiting the analysis to public sites only. Windows increases from 95% to 98% HTTPS, and both Android and Mac increase to over 99% HTTPS.

In recognition of the reduced risk HTTP to private sites represents, last year we introduced a variant of “Always Use Secure Connections” for public sites only. For users who frequently access private sites (such as those in enterprise settings, or web developers), excluding warnings on private sites significantly reduces the volume of warnings those users will see. Simultaneously, for users who do not access private sites frequently, this mode introduces only a small reduction in protection. This is the variant we intend to enable for all users next year.

“Always Use Secure Connections,” available at chrome://settings/security

In Chrome 141, we experimented with enabling “Always Use Secure Connections” for public sites by default for a small percentage of users. We wanted to validate our expectations that this setting keeps users safer without burdening them with excessive warnings.

Analyzing the data from the experiment, we confirmed that the number of warnings seen by any users is considerably lower than 3% of navigations—in fact, the median user sees fewer than one warning per week, and the ninety-fifth percentile user sees fewer than three warnings per week..

Understanding HTTP usage

Once “Always Use Secure Connections” is the default and additional sites migrate away from HTTP, we expect the actual warning volume to be even lower than it is now. In parallel to our experiments, we have reached out to a number of companies responsible for the most HTTP navigations, and expect that they will be able to migrate away from HTTP before the change in Chrome 154. For many of these organizations, transitioning to HTTPS isn't disproportionately hard, but simply has not received attention. For example, many of these sites use HTTP only for navigations that immediately redirect to HTTPS sites—an insecure interaction which was previously completely invisible to users.

Another current use case for HTTP is to avoid mixed content blocking when accessing devices on the local network. Private addresses, as discussed above, often do not have trusted HTTPS certificates, due to the difficulties of validating ownership of a non-unique name. This means most local network traffic is over HTTP, and cannot be initiated from an HTTPS page—the HTTP traffic counts as insecure mixed content, and is blocked. One common use case for needing to access the local network is to configure a local network device, e.g. the manufacturer might host a configuration portal at config.example.com, which then sends requests to a local device to configure it.

Previously, these types of pages needed to be hosted without HTTPS to avoid mixed content blocking. However, we recently introduced a local network access permission, which both prevents sites from accessing the user’s local network without consent, but also allows an HTTPS site to bypass mixed content checks for the local network once the permission has been granted. This can unblock migrating these domains to HTTPS.

Changes in Chrome

We will enable the "Always Use Secure Connections" setting in its public-sites variant by default in October 2026, with the release of Chrome 154. Prior to enabling it by default for all users, in Chrome 147, releasing in April 2026, we will enable Always Use Secure Connections in its public-sites variant for the over 1 billion users who have opted-in to Enhanced Safe Browsing protections in Chrome.

While it is our hope and expectation that this transition will be relatively painless for most users, users will still be able to disable the warnings by disabling the "Always Use Secure Connections" setting.

If you are a website developer or IT professional, and you have users who may be impacted by this feature, we very strongly recommend enabling the "Always Use Secure Connections" setting today to help identify sites that you may need to work to migrate. IT professionals may find it useful to read our additional resources to better understand the circumstances where warnings will be shown, how to mitigate them, and how organizations that manage Chrome clients (like enterprises or educational institutions) can ensure that Chrome shows the right warnings to meet those organizations' needs.

Looking Forward

While we believe that warning on insecure public sites represents a significant step forward for the security of the web, there is still more work to be done. In the future, we hope to work to further reduce barriers to adoption of HTTPS, especially for local network sites. This work will hopefully enable even more robust HTTP protections down the road.

Posted by Chris Thompson, Mustafa Emre Acer, Serena Chen, Joe DeBlasio, Emily Stark and David Adrian, Chrome Security Team

Posted by Elie Bursztein and Marianna Tishchenko, Google Privacy, Safety and Security Team

Posted by Daniel Moghimi

Posted by Eric Lynch, Senior Product Manager, Android Security, and Sherif Hanna, Group Product Manager, Google C2PA Core

At Made by Google 2025, we announced that the new Google Pixel 10 phones will support C2PA Content Credentials in Pixel Camera and Google Photos. This announcement represents a series of steps towards greater digital media transparency:

• The Pixel 10 lineup is the first to have Content Credentials built in across every photo created by Pixel Camera.
• The Pixel Camera app achieved Assurance Level 2, the highest security rating currently defined by the C2PA Conformance Program. Assurance Level 2 for a mobile app is currently only possible on the Android platform.
• A private-by-design approach to C2PA certificate management, where no image or group of images can be related to one another or the person who created them.
• Pixel 10 phones support on-device trusted time-stamps, which ensures images captured with your native camera app can be trusted after the certificate expires, even if they were captured when your device was offline.

These capabilities are powered by Google Tensor G5, Titan M2 security chip, the advanced hardware-backed security features of the Android platform, and Pixel engineering expertise.

In this post, we’ll break down our architectural blueprint for bringing a new level of trust to digital media, and how developers can apply this model to their own apps on Android.

A New Approach to Content Credentials

Generative AI can help us all to be more creative, productive, and innovative. But it can be hard to tell the difference between content that’s been AI-generated, and content created without AI. The ability to verify the source and history—or provenance—of digital content is more important than ever.

Content Credentials convey a rich set of information about how media such as images, videos, or audio files were made, protected by the same digital signature technology that has secured online transactions and mobile apps for decades. It empowers users to identify AI-generated (or altered) content, helping to foster transparency and trust in generative AI. It can be complemented by watermarking technologies such as SynthID.

Content Credentials are an industry standard backed by a broad coalition of leading companies for securely conveying the origin and history of media files. The standard is developed by the Coalition for Content Provenance and Authenticity (C2PA), of which Google is a steering committee member.

The traditional approach to classifying digital image content has focused on categorizing content as “AI” vs. “not AI”. This has been the basis for many legislative efforts, which have required the labeling of synthetic media. This traditional approach has drawbacks, as described in Chapter 5 of this seminal report by Google. Research shows that if only synthetic content is labeled as “AI”, then users falsely believe unlabeled content is “not AI”, a phenomenon called “the implied truth effect”. This is why Google is taking a different approach to applying C2PA Content Credentials.

Instead of categorizing digital content into a simplistic “AI” vs. “not AI”, Pixel 10 takes the first steps toward implementing our vision of categorizing digital content as either i) media that comes with verifiable proof of how it was made or ii) media that doesn't.

• Pixel Camera attaches Content Credentials to any JPEG photo capture, with the appropriate description as defined by the Content Credentials specification for each capture mode.
• Google Photos attaches Content Credentials to JPEG images that already have Content Credentials and are edited using AI or non-AI tools, and also to any images that are edited using AI tools. It will validate and display Content Credentials under a new section in the About panel, if the JPEG image being viewed contains this data. Learn more about it in Google Photos Help.

Given the broad range of scenarios in which Content Credentials are attached by these apps, we designed our C2PA implementation architecture from the onset to be:

1. Secure from silicon to applications
2. Verifiable, not personally identifiable
3. Useable offline

Secure from Silicon to Applications

Good actors in the C2PA ecosystem are motivated to ensure that provenance data is trustworthy. C2PA Certification Authorities (CAs), such as Google, are incentivized to only issue certificates to genuine instances of apps from trusted developers in order to prevent bad actors from undermining the system. Similarly, app developers want to protect their C2PA claim signing keys from unauthorized use. And of course, users want assurance that the media files they rely on come from where they claim. For these reasons, the C2PA defined the Conformance Program.

The Pixel Camera application on the Pixel 10 lineup has achieved Assurance Level 2, the highest security rating currently defined by the C2PA Conformance Program. This was made possible by a strong set of hardware-backed technologies, including Tensor G5 and the certified Titan M2 security chip, along with Android’s hardware-backed security APIs. Only mobile apps running on devices that have the necessary silicon features and Android APIs can be designed to achieve this assurance level. We are working with C2PA to help define future assurance levels that will push protections even deeper into hardware.

Achieving Assurance Level 2 requires verifiable, difficult-to-forge evidence. Google has built an end-to-end system on Pixel 10 devices that verifies several key attributes. However, the security of any claim is fundamentally dependent on the integrity of the application and the OS, an integrity that relies on both being kept current with the latest security patches.

• Hardware Trust: Android Key Attestation in Pixel 10 is built on support for Device Identifier Composition Engine (DICE) by Tensor, and Remote Key Provisioning (RKP) to establish a trust chain from the moment the device starts up to the OS, stamping out the most common forms of abuse on Android.
• Genuine Device and Software: Aided by the hardware trust described above, Android Key Attestation allows Google C2PA Certification Authorities (CAs) to verify that they are communicating with a genuine physical device. It also allows them to verify the device has booted securely into a Play Protect Certified version of Android, and verify how recently the operating system, bootloader, and system software and firmware were patched for security vulnerabilities.
• Genuine Application: Hardware-backed Android Key Attestation certificates include the package name and signing certificates associated with the app that requested the generation of the C2PA signing key, allowing Google C2PA CAs to check that the app requesting C2PA claim signing certificates is a trusted, registered app.
• Tamper-Resistant Key Storage: On Pixel, C2PA claim signing keys are generated and stored using Android StrongBox in the Titan M2 security chip. Titan M2 is Common Criteria PP.0084 AVA_VAN.5 certified, meaning that it is strongly resistant to extracting or tampering with the cryptographic keys stored in it. Android Key Attestation allows Google C2PA CAs to verify that private keys were indeed created inside this hardware-protected vault before issuing certificates for their public key counterparts.

The C2PA Conformance Program requires verifiable artifacts backed by a hardware Root of Trust, which Android provides through features like Key Attestation. This means Android developers can leverage these same tools to build apps that meet this standard for their users.

Privacy Built on a Foundation of Trust: Verifiable, Not Personally Identifiable

The robust security stack we described is the foundation of privacy. But Google takes steps further to ensure your privacy even as you use Content Credentials, which required solving two additional challenges:

Challenge 1: Server-side Processing of Certificate Requests. Google’s C2PA Certification Authorities must certify new cryptographic keys generated on-device. To prevent fraud, these certificate enrollment requests need to be authenticated. A more common approach would require user accounts for authentication, but this would create a server-side record linking a user's identity to their C2PA certificates—a privacy trade-off we were unwilling to make.

Our Solution: Anonymous, Hardware-Backed Attestation. We solve this with Android Key Attestation, which allows Google CAs to verify what is being used (a genuine app on a secure device) without ever knowing who is using it (the user). Our CAs also enforce a strict no-logging policy for information like IP addresses that could tie a certificate back to a user.

Challenge 2: The Risk of Traceability Through Key Reuse. A significant privacy risk in any provenance system is traceability. If the same device or app-specific cryptographic key is used to sign multiple photos, those images can be linked by comparing the key. An adversary could potentially connect a photo someone posts publicly under their real name with a photo they post anonymously, deanonymizing the creator.

Our Solution: Unique Certificates. We eliminate this threat with a maximally private approach. Each key and certificate is used to sign exactly one image. No two images ever share the same public key, a "One-and-Done" Certificate Management Strategy, making it cryptographically impossible to link them. This engineering investment in user privacy is designed to set a clear standard for the industry.

Overall, you can use Content Credentials on Pixel 10 without fear that another person or Google could use it to link any of your images to you or one another.

Ready to Use When You Are - Even Offline

Implementations of Content Credentials use trusted time-stamps to ensure the credentials can be validated even after the certificate used to produce them expires. Obtaining these trusted time-stamps typically requires connectivity to a Time-Stamping Authority (TSA) server. But what happens if the device is offline?

This is not a far-fetched scenario. Imagine you’ve captured a stunning photo of a remote waterfall. The image has Content Credentials that prove that it was captured by a camera, but the cryptographic certificate used to produce them will eventually expire. Without a time-stamp, that proof could become untrusted, and you're too far from a cell signal, which is required to receive one.

To solve this, Pixel developed an on-device, offline TSA.

Powered by the security features of Tensor, Pixel maintains a trusted clock in a secure environment, completely isolated from the user-controlled one in Android. The clock is synchronized regularly from a trusted source while the device is online, and is maintained even after the device goes offline (as long as the phone remains powered on). This allows your device to generate its own cryptographically-signed time-stamps the moment you press the shutter—no connection required. It ensures the story behind your photo remains verifiable and trusted after its certificate expires, whether you took it in your living room or at the top of a mountain.

Building a More Trustworthy Ecosystem, Together

C2PA Content Credentials are not the sole solution for identifying the provenance of digital media. They are, however, a tangible step toward more media transparency and trust as we continue to unlock more human creativity with AI.

In our initial implementation of Content Credentials on the Android platform and Pixel 10 lineup, we prioritized a higher standard of privacy, security, and usability. We invite other implementers of Content Credentials to evaluate our approach and leverage these same foundational hardware and software security primitives. The full potential of these technologies can only be realized through widespread ecosystem adoption.

We look forward to adding Content Credentials across more Google products in the near future.

Posted by Dave Kleidermacher, VP Engineering, Android Security & Privacy

Today marks a watershed moment and new benchmark for open-source security and the future of consumer electronics. Google is proud to announce that protected KVM (pKVM), the hypervisor that powers the Android Virtualization Framework, has officially achieved SESIP Level 5 certification. This makes pKVM the first software security system designed for large-scale deployment in consumer electronics to meet this assurance bar.

Supporting Next-Gen Android Features

The implications for the future of secure mobile technology are profound. With this level of security assurance, Android is now positioned to securely support the next generation of high-criticality isolated workloads. This includes vital features, such as on-device AI workloads that can operate on ultra-personalized data, with the highest assurances of privacy and integrity.

This certification required a hands-on evaluation by Dekra, a globally recognized cybersecurity certification lab, which conducted an evaluation against the TrustCB SESIP scheme, compliant to EN-17927. Achieving Security Evaluation Standard for IoT Platforms (SESIP) Level 5 is a landmark because it incorporates AVA_VAN.5, the highest level of vulnerability analysis and penetration testing under the ISO 15408 (Common Criteria) standard. A system certified to this level has been evaluated to be resistant to highly skilled, knowledgeable, well-motivated, and well-funded attackers who may have insider knowledge and access.

This certification is the cornerstone of the next-generation of Android’s multi-layered security strategy. Many of the TEEs (Trusted Execution Environments) used in the industry have not been formally certified or have only achieved lower levels of security assurance. This inconsistency creates a challenge for developers looking to build highly critical applications that require a robust and verifiable level of security. The certified pKVM changes this paradigm entirely. It provides a single, open-source, and exceptionally high-quality firmware base that all device manufacturers can build upon.

Looking ahead, Android device manufacturers will be required to use isolation technology that meets this same level of security for various security operations that the device relies on. Protected KVM ensures that every user can benefit from a consistent, transparent, and verifiably secure foundation.

A Collaborative Effort

This achievement represents just one important aspect of the immense, multi-year dedication from the Linux and KVM developer communities and multiple engineering teams at Google developing pKVM and AVF. We look forward to seeing the open-source community and Android ecosystem continue to build on this foundation, delivering a new era of high-assurance mobile technology for users.

Posted by Matthew Suozzo, Google Open Source Security Team (GOSST)

Posted by David Adrian, Javier Castro & Peter Kotwicz, Chrome Security Team

Android recently announced Advanced Protection, which extends Google’s Advanced Protection Program to a device-level security setting for Android users that need heightened security—such as journalists, elected officials, and public figures. Advanced Protection gives you the ability to activate Google’s strongest security for mobile devices, providing greater peace of mind that you’re better protected against the most sophisticated threats.

Advanced Protection acts as a single control point for at-risk users on Android that enables important security settings across applications, including many of your favorite Google apps, including Chrome. In this post, we’d like to do a deep dive into the Chrome features that are integrated with Advanced Protection, and how enterprises and users outside of Advanced Protection can leverage them.

Android Advanced Protection integrates with Chrome on Android in three main ways:

• Enables the “Always Use Secure Connections” setting for both public and private sites, so that users are protected from attackers reading confidential data or injecting malicious content into insecure plaintext HTTP connections. Insecure HTTP represents less than 1% of page loads for Chrome on Android.
• Enables full Site Isolation on mobile devices with 4GB+ RAM, so that potentially malicious sites are never loaded in the same process as legitimate websites. Desktop Chrome clients already have full Site Isolation.
• Reduces attack surface by disabling Javascript optimizations, so that Chrome has a smaller attack surface and is harder to exploit.

Let’s take a look at all three, learn what they do, and how they can be controlled outside of Advanced Protection.

Always Use Secure Connections

“Always Use Secure Connections” (also known as HTTPS-First Mode in blog posts and HTTPS-Only Mode in the enterprise policy) is a Chrome setting that forces HTTPS wherever possible, and asks for explicit permission from you before connecting to a site insecurely. There may be attackers attempting to interpose on connections on any network, whether that network is a coffee shop, airport, or an Internet backbone. This setting protects users from these attackers reading confidential data and injecting malicious content into otherwise innocuous webpages. This is particularly useful for Advanced Protection users, since in 2023, plaintext HTTP was used as an exploitation vector during the Egyptian election.

Beyond Advanced Protection, we previously posted about how our goal is to eventually enable “Always Use Secure Connections” by default for all Chrome users. As we work towards this goal, in the last two years we have quietly been enabling it in more places beyond Advanced Protection, to help protect more users in risky situations, while limiting the number of warnings users might click through:

• We added a new variant of the setting that only warns on public sites, and doesn’t warn on local networks or single-label hostnames (e.g. 192.168.0.1, shortlink/, 10.0.0.1). These names often cannot be issued a publicly-trusted HTTPS certificate. This variant protects against most threats—accessing a public website insecurely—but still allows for users to access local sites, which may be on a more trusted network, without seeing a warning.
• We’ve automatically enabled “Always Use Secure Connections” for public sites in Incognito Mode for the last year, since Chrome 127 in June 2024.
• We automatically prevent downgrades from HTTPS to plaintext HTTP on sites that Chrome knows you typically access over HTTPS (a heuristic version of the HSTS header), since Chrome 133 in January 2025.

Always Use Secure Connections has two modes—warn on insecure public sites, and warn on any insecure site.

Any user can enable “Always Use Secure Connections” in the Chrome Privacy and Security settings, regardless of if they’re using Advanced Protection. Users can choose if they would like to warn on any insecure site, or only insecure public sites. Enterprises can opt their fleet into either mode, and set exceptions using the HTTPSOnlyMode and HTTPAllowlist policies, respectively. Website operators should protect their users' confidentiality, ensure their content is delivered exactly as they intended, and avoid warnings, by deploying HTTPS.

Posted by Google GenAI Security Team

Posted by Chrome Root Program, Chrome Security Team

Note: Google Chrome communicated its removal of default trust of Chunghwa Telecom and Netlock in the public forum on May 30, 2025.

The Chrome Root Program Policy states that Certification Authority (CA) certificates included in the Chrome Root Store must provide value to Chrome end users that exceeds the risk of their continued inclusion. It also describes many of the factors we consider significant when CA Owners disclose and respond to incidents. When things don’t go right, we expect CA Owners to commit to meaningful and demonstrable change resulting in evidenced continuous improvement.

Chrome's confidence in the reliability of Chunghwa Telecom and Netlock as CA Owners included in the Chrome Root Store has diminished due to patterns of concerning behavior observed over the past year. These patterns represent a loss of integrity and fall short of expectations, eroding trust in these CA Owners as publicly-trusted certificate issuers trusted by default in Chrome. To safeguard Chrome’s users, and preserve the integrity of the Chrome Root Store, we are taking the following action.

Upcoming change in Chrome 139 and higher:

• Transport Layer Security (TLS) server authentication certificates validating to the following root CA certificates whose earliest Signed Certificate Timestamp (SCT) is dated after July 31, 2025 11:59:59 PM UTC, will no longer be trusted by default.
• OU=ePKI Root Certification Authority,O=Chunghwa Telecom Co., Ltd.,C=TW
• CN=HiPKI Root CA - G1,O=Chunghwa Telecom Co., Ltd.,C=TW
• CN=NetLock Arany (Class Gold) Főtanúsítvány,OU=Tanúsítványkiadók (Certification Services),O=NetLock Kft.,L=Budapest,C=HU
• TLS server authentication certificates validating to the above set of roots whose earliest SCT is on or before July 31, 2025 11:59:59 PM UTC, will be unaffected by this change.

This approach attempts to minimize disruption to existing subscribers using a previously announced Chrome feature to remove default trust based on the SCTs in certificates.

Additionally, should a Chrome user or enterprise explicitly trust any of the above certificates on a platform and version of Chrome relying on the Chrome Root Store (e.g., explicit trust is conveyed through a Group Policy Object on Windows), the SCT-based constraints described above will be overridden and certificates will function as they do today.

To further minimize risk of disruption, website operators are encouraged to review the “Frequently Asked Questions" listed below.

Why is Chrome taking action?

CAs serve a privileged and trusted role on the internet that underpin encrypted connections between browsers and websites. With this tremendous responsibility comes an expectation of adhering to reasonable and consensus-driven security and compliance expectations, including those defined by the CA/Browser Forum TLS Baseline Requirements.

Over the past several months and years, we have observed a pattern of compliance failures, unmet improvement commitments, and the absence of tangible, measurable progress in response to publicly disclosed incident reports. When these factors are considered in aggregate and considered against the inherent risk each publicly-trusted CA poses to the internet, continued public trust is no longer justified.

When will this action happen?

The action of Chrome, by default, no longer trusting new TLS certificates issued by these CAs will begin on approximately August 1, 2025, affecting certificates issued at that point or later.

This action will occur in Versions of Chrome 139 and greater on Windows, macOS, ChromeOS, Android, and Linux. Apple policies prevent the Chrome Certificate Verifier and corresponding Chrome Root Store from being used on Chrome for iOS.

What is the user impact of this action?

By default, Chrome users in the above populations who navigate to a website serving a certificate from Chunghwa Telecom or Netlock issued after July 31, 2025 will see a full page interstitial similar to this one.

Certificates issued by other CAs are not impacted by this action.

How can a website operator tell if their website is affected?

Website operators can determine if they are affected by this action by using the Chrome Certificate Viewer.

Use the Chrome Certificate Viewer

• Navigate to a website (e.g., https://www.google.com)
• Click the “Tune" icon
• Click “Connection is Secure"
• Click “Certificate is Valid" (the Chrome Certificate Viewer will open)
• Website owner action is not required, if the “Organization (O)” field listed beneath the “Issued By" heading does not contain “Chunghwa Telecom" , “行政院” , “NETLOCK Ltd.”, or “NETLOCK Kft.”
• Website owner action is required, if the “Organization (O)” field listed beneath the “Issued By" heading contains “Chunghwa Telecom" , “行政院” , “NETLOCK Ltd.”, or “NETLOCK Kft.”

What does an affected website operator do?

We recommend that affected website operators transition to a new publicly-trusted CA Owner as soon as reasonably possible. To avoid adverse website user impact, action must be completed before the existing certificate(s) expire if expiry is planned to take place after July 31, 2025.

While website operators could delay the impact of blocking action by choosing to collect and install a new TLS certificate issued from Chunghwa Telecom or Netlock before Chrome’s blocking action begins on August 1, 2025, website operators will inevitably need to collect and install a new TLS certificate from one of the many other CAs included in the Chrome Root Store.

Can I test these changes before they take effect?

Yes.

A command-line flag was added beginning in Chrome 128 that allows administrators and power users to simulate the effect of an SCTNotAfter distrust constraint as described in this blog post.

How to: Simulate an SCTNotAfter distrust

1. Close all open versions of Chrome

2. Start Chrome using the following command-line flag, substituting variables described below with actual values

3. Evaluate the effects of the flag with test websites

Learn more about command-line flags here.

I use affected certificates for my internal enterprise network, do I need to do anything?

Beginning in Chrome 127, enterprises can override Chrome Root Store constraints like those described in this blog post by installing the corresponding root CA certificate as a locally-trusted root on the platform Chrome is running (e.g., installed in the Microsoft Certificate Store as a Trusted Root CA).

How do enterprises add a CA as locally-trusted?

Customer organizations should use this enterprise policy or defer to platform provider guidance for trusting root CA certificates.

What about other Google products?

Other Google product team updates may be made available in the future.

Posted by Craig Gidney, Quantum Research Scientist, and Sophie Schmieg, Senior Staff Cryptography Engineer 

Posted by Dave Kleidermacher, VP Engineering, Android Security and Privacy

Android’s intelligent protections keep you safe from everyday dangers. Our dedication to your security is validated by security experts, who consistently rank top Android devices highest in security, and score Android smartphones, led by the Pixel 9 Pro, as leaders in anti-fraud efficacy.

Android is always developing new protections to keep you, your device, and your data safe. Today, we’re announcing new features and enhancements that build on our industry-leading protections to help keep you safe from scams, fraud, and theft on Android.

Smarter protections against phone call scams

Our research shows that phone scammers often try to trick people into performing specific actions to initiate a scam, like changing default device security settings or granting elevated permissions to an app. These actions can result in spying, fraud, and other abuse by giving an attacker deeper access to your device and data. To combat phone scammers, we’re working to block specific actions and warn you of these sophisticated attempts. This happens completely on device and is applied only with conversations with non-contacts.

Android’s new in-call protections¹ provide an additional layer of defense, preventing you from taking risky security actions during a call like:

• Disabling Google Play Protect, Android’s built-in security protection, that is on by default and continuously scans for malicious app behavior, no matter the download source.
• Sideloading an app for the first time from a web browser, messaging app or other source – which may not have been vetted for security and privacy by Google.
• Granting accessibility permissions, which can give a newly downloaded malicious app access to gain control over the user's device and steal sensitive/private data, like banking information.

And if you’re screen sharing during a phone call, Android will now automatically prompt you to stop sharing at the end of a call. These protections help safeguard you against scammers that attempt to gain access to sensitive information to conduct fraud.

Piloting enhanced in-call protection for banking apps

Screen sharing scams are becoming quite common, with fraudsters often impersonating banks, government agencies, and other trusted institutions – using screen sharing to guide users to perform costly actions such as mobile banking transfers. To better protect you from these attacks, we’re piloting new in-call protections for banking apps, starting in the UK.

When you launch a participating banking app while screen sharing with an unknown contact, your Android device will warn you about the potential dangers and give you the option to end the call and to stop screen sharing with one tap.

This feature will be enabled automatically for participating banking apps whenever you're on a phone call with an unknown contact on Android 11+ devices. We are working with UK banks Monzo, NatWest and Revolut to pilot this feature for their customers in the coming weeks and will assess the results of the pilot ahead of a wider roll out.

Making real-time Scam Detection in Google Messages even more intelligent

We recently launched AI-powered Scam Detection in Google Messages and Phone by Google to protect you from conversational scams that might sound innocent at first, but turn malicious and can lead to financial loss or data theft. When Scam Detection discovers a suspicious conversation pattern, it warns you in real-time so you can react before falling victim to a costly scam.

AI-powered Scam Detection is always improving to help keep you safe while also keeping your privacy in mind. With Google’s advanced on-device AI, your conversations stay private to you. All message processing remains on-device and you’re always in control. You can turn off Spam Protection, which includes Scam Detection, in your Google Messages at any time.

Prior to targeting conversational scams, Scam Detection in Google Messages focused on analyzing and detecting package delivery and job seeking scams. We’ve now expanded our detections to help protect you from a wider variety of sophisticated scams including:

• Toll road and other billing fee scams
• Crypto scams
• Financial impersonation scams
• Gift card and prize scams
• Technical support scams
• And more

These enhancements apply to all Google Messages users.

Fighting fraud and impersonation with Key Verifier

To help protect you from scammers who try to impersonate someone you know, we’re launching a helpful tool called Key Verifier. The feature allows you and the person you’re messaging to verify the identity of the other party through public encryption keys, protecting your end-to-end encrypted messages in Google Messages. By verifying contact keys in your Google Contacts app (through a QR code scanning or number comparison), you can have an extra layer of assurance that the person on the other end is genuine and that your conversation is private with them.

Key Verifier provides a visual way for you and your contact to quickly confirm that your secret keys match, strengthening your confidence that you’re communicating with the intended recipient and not a scammer. For example, if an attacker gains access to a friend’s phone number and uses it on another device to send you a message – which can happen as a result of a SIM swap attack – their contact's verification status will be marked as no longer verified in the Google Contacts app, suggesting your friend’s account may be compromised or has been changed. Key Verifier will launch later this summer in Google Messages on Android 10+ devices.

Comprehensive mobile theft protection, now even stronger

Physical device theft can lead to financial fraud and data theft, with the value of your banking and payment information many times exceeding the value of your phone. This is one of the reasons why last year we launched the mobile industry’s most comprehensive suite of theft protection features to protect you before, during, and after a theft. Since launch, our theft protection features have helped protect data on hundreds of thousands of devices that may have fallen into the wrong hands. This includes devices that were locked by Remote Lock or Theft Detection Lock and remained locked for over 48 hours.

Most recently, we launched Identity Check for Pixel and Samsung One UI 7 devices, providing an extra layer of security even if your PIN or password is compromised. This protection will also now be available from more device manufacturers on supported devices that upgrade to Android 16.

Coming later this year, we’re further hardening Factory Reset protections, which will restrict all functionalities on devices that are reset without the owner’s authorization. You'll also gain more control over our Remote Lock feature with the addition of a security challenge question, helping to prevent unauthorized actions.

We’re also enhancing your security against thieves in Android 16 by providing more protection for one-time passwords that are received when your phone is locked. In higher risk scenarios², Android will hide one-time passwords on your lock screen, ensuring that only you can see them after unlocking your device.

Advanced Protection: Google’s strongest security for mobile devices

Protecting users who need heightened security has been a long-standing commitment at Google, which is why we have our Advanced Protection Program that provides Google’s strongest protections against targeted attacks.

To enhance these existing device defenses, Android 16 extends Advanced Protection with a device-level security setting for Android users. Whether you’re an at-risk individual – such as a journalist, elected official, or public figure – or you just prioritize security, Advanced Protection gives you the ability to activate Google’s strongest security for mobile devices, providing greater peace of mind that you’re protected against the most sophisticated threats.

Advanced Protection is available on devices with Android 16. Learn more in our blog.

More intelligent defenses against bad apps with Google Play Protect

One way malicious developers try to trick people is by hiding or changing their app icon, making unsafe apps more difficult to find and remove. Now, Google Play Protect live threat detection will catch apps and alert you when we detect this deceptive behavior. This feature will be available to Google Pixel 6+ and a selection of new devices from other manufacturers in the coming months.

Google Play Protect always checks each app before it gets installed on your device, regardless of the install source. It conducts real-time scanning of an app, enhanced by on-device machine learning, when users try to install an app that has never been seen by Google Play Protect to help detect emerging threats.

We’ve made Google Play Protect’s on-device capabilities smarter to help us identify more malicious applications even faster to keep you safe. Google Play Protect now uses a new set of on-device rules to specifically look for text or binary patterns to quickly identify malware families. If an app shows these malicious patterns, we can alert you before you even install it. And to keep you safe from new and emerging malware and their variants, we will update these rules frequently for better classification over time.

This update to Google Play Protect is now available globally for all Android users with Google Play services.

Always advancing Android security

In addition to new features that come in numbered Android releases, we're constantly enhancing your protection on Android through seamless Google Play services updates and other improvements, ensuring you benefit from the latest security advancements continuously. This allows us to rapidly deploy critical defenses and keep you ahead of emerging threats, making your Android experience safer every day.

Through close collaboration with our partners across the Android ecosystem and the broader security community, we remain focused on bringing you security enhancements and innovative new features to help keep you safe.

Notes

Posted by Il-Sung Lee, Group Product Manager, Android Security

Protecting users who need heightened security has been a long-standing commitment at Google, which is why we have our Advanced Protection Program that provides Google’s strongest protections against targeted attacks.

To enhance these existing device defenses, Android 16 extends Advanced Protection with a device-level security setting for Android users. Whether you’re an at-risk individual – such as a journalist, elected official, or public figure – or you just prioritize security, Advanced Protection gives you the ability to activate Google’s strongest security for mobile devices, providing greater peace of mind that you’re protected against the most sophisticated threats.

Simple to activate, powerful in protection

Advanced Protection ensures all of Android's highest security features are enabled and are seamlessly working together to safeguard you against online attacks, harmful apps, and data risks.

Advanced Protection activates a powerful array of security features, combining new capabilities with pre-existing ones that have earned top ratings in security comparisons, all designed to protect your device across several critical areas.

We're also introducing innovative, Android-specific features, such as Intrusion Logging. This industry-first feature securely backs up device logs in a privacy-preserving and tamper-resistant way, accessible only to the user. These logs enable a forensic analysis if a device compromise is ever suspected.

Advanced Protection gives users:

• Best-in-class protection, minimal disruption: Advanced Protection gives users the option to equip their devices with Android’s most effective security features for proactive defense, with a user-friendly and low-friction experience.
• Easy activation: Advanced Protection makes security easy and accessible. You don’t need to be a security expert to benefit from enhanced security.
• Defense-in-depth: Once a user turns on Advanced Protection, the system prevents accidental or malicious disablement of the individual security features under the Advanced Protection umbrella. This reflects a "defense-in-depth" strategy, where multiple security layers work together.
• Seamless security integration with apps: Advanced Protection acts as a single control point that enables important security settings across many of your favorite Google apps, including Chrome, Google Message, and Phone by Google. Advanced Protection will also incorporate third-party applications that choose to integrate in the future.
  

How your Android device becomes fortified with Advanced Protection

Advanced Protection manages the following existing and new security features for your device, ensuring they are activated and cannot be disabled across critical protection areas:

Continuously evolving Advanced Protection

With the release of Android 16, users who choose to activate Advanced Protection will gain immediate access to a core suite of enhanced security features. Additional Advanced Protection features like Intrusion Logging, USB protection, the option to disable auto-reconnect to insecure networks, and integration with Scam Detection for Phone by Google will become available later this year.

We are committed to continuously expanding the security and privacy capabilities within Advanced Protection, so users can benefit from the best of Android’s powerful security features.

Posted by Jasika Bawa, Andy Lim, and Xinghui Lu, Google Chrome Security

Tech support scams are an increasingly prevalent form of cybercrime, characterized by deceptive tactics aimed at extorting money or gaining unauthorized access to sensitive data. In a tech support scam, the goal of the scammer is to trick you into believing your computer has a serious problem, such as a virus or malware infection, and then convince you to pay for unnecessary services, software, or grant them remote access to your device. Tech support scams on the web often employ alarming pop-up warnings mimicking legitimate security alerts. We've also observed them to use full-screen takeovers and disable keyboard and mouse input to create a sense of crisis.

Chrome has always worked with Google Safe Browsing to help keep you safe online. Now, with this week's launch of Chrome 137, Chrome will offer an additional layer of protection using the on-device Gemini Nano large language model (LLM). This new feature will leverage the LLM to generate signals that will be used by Safe Browsing in order to deliver higher confidence verdicts about potentially dangerous sites like tech support scams.

Initial research using LLMs has shown that they are relatively effective at understanding and classifying the varied, complex nature of websites. As such, we believe we can leverage LLMs to help detect scams at scale and adapt to new tactics more quickly. But why on-device? Leveraging LLMs on-device allows us to see threats when users see them. We’ve found that the average malicious site exists for less than 10 minutes, so on-device protection allows us to detect and block attacks that haven't been crawled before. The on-device approach also empowers us to see threats the way users see them. Sites can render themselves differently for different users, often for legitimate purposes (e.g. to account for device differences, offer personalization, provide time-sensitive content), but sometimes for illegitimate purposes (e.g. to evade security crawlers) – as such, having visibility into how sites are presenting themselves to real users enhances our ability to assess the web.

How it works

At a high level, here's how this new layer of protection works.

Overview of how on-device LLM assistance in mitigating scams works

When a user navigates to a potentially dangerous page, specific triggers that are characteristic of tech support scams (for example, the use of the keyboard lock API) will cause Chrome to evaluate the page using the on-device Gemini Nano LLM. Chrome provides the LLM with the contents of the page that the user is on and queries it to extract security signals, such as the intent of the page. This information is then sent to Safe Browsing for a final verdict. If Safe Browsing determines that the page is likely to be a scam based on the LLM output it receives from the client, in addition to other intelligence and metadata about the site, Chrome will show a warning interstitial.

This is all done in a way that preserves performance and privacy. In addition to ensuring that the LLM is only triggered sparingly and run locally on the device, we carefully manage resource consumption by considering the number of tokens used, running the process asynchronously to avoid interrupting browser activity, and implementing throttling and quota enforcement mechanisms to limit GPU usage. LLM-summarized security signals are only sent to Safe Browsing for users who have opted-in to the Enhanced Protection mode of Safe Browsing in Chrome, giving them protection against threats Google may not have seen before. Standard Protection users will also benefit indirectly from this feature as we add newly discovered dangerous sites to blocklists.

Future considerations

The scam landscape continues to evolve, with bad actors constantly adapting their tactics. Beyond tech support scams, in the future we plan to use the capabilities described in this post to help detect other popular scam types, such as package tracking scams and unpaid toll scams. We also plan to utilize the growing power of Gemini to extract additional signals from website content, which will further enhance our detection capabilities. To protect even more users from scams, we are working on rolling out this feature to Chrome on Android later this year. And finally, we are collaborating with our research counterparts to explore solutions to potential exploits such as prompt injection in content and timing bypass.

Posted by Elie Burzstein and Marianna Tishchenko, Sec-Gemini team

Posted by Mihai Maruseac, Google Open Source Security Team (GOSST)

Posted by Chrome Root Program, Chrome Security Team

The Chrome Root Program launched in 2022 as part of Google’s ongoing commitment to upholding secure and reliable network connections in Chrome. We previously described how the Chrome Root Program keeps users safe, and described how the program is focused on promoting technologies and practices that strengthen the underlying security assurances provided by Transport Layer Security (TLS). Many of these initiatives are described on our forward looking, public roadmap named “Moving Forward, Together.”

At a high-level, “Moving Forward, Together” is our vision of the future. It is non-normative and considered distinct from the requirements detailed in the Chrome Root Program Policy. It’s focused on themes that we feel are essential to further improving the Web PKI ecosystem going forward, complementing Chrome’s core principles of speed, security, stability, and simplicity. These themes include:

• Encouraging modern infrastructures and agility
• Focusing on simplicity
• Promoting automation
• Reducing mis-issuance
• Increasing accountability and ecosystem integrity
• Streamlining and improving domain validation practices
• Preparing for a "post-quantum" world

Earlier this month, two “Moving Forward, Together” initiatives became required practices in the CA/Browser Forum Baseline Requirements (BRs). The CA/Browser Forum is a cross-industry group that works together to develop minimum requirements for TLS certificates. Ultimately, these new initiatives represent an improvement to the security and agility of every TLS connection relied upon by Chrome users.

If you’re unfamiliar with HTTPS and certificates, see the “Introduction” of this blog post for a high-level overview.

Multi-Perspective Issuance Corroboration

Before issuing a certificate to a website, a Certification Authority (CA) must verify the requestor legitimately controls the domain whose name will be represented in the certificate. This process is referred to as "domain control validation" and there are several well-defined methods that can be used. For example, a CA can specify a random value to be placed on a website, and then perform a check to verify the value’s presence has been published by the certificate requestor.

Despite the existing domain control validation requirements defined by the CA/Browser Forum, peer-reviewed research authored by the Center for Information Technology Policy (CITP) of Princeton University and others highlighted the risk of Border Gateway Protocol (BGP) attacks and prefix-hijacking resulting in fraudulently issued certificates. This risk was not merely theoretical, as it was demonstrated that attackers successfully exploited this vulnerability on numerous occasions, with just one of these attacks resulting in approximately $2 million dollars of direct losses.

Multi-Perspective Issuance Corroboration (referred to as "MPIC") enhances existing domain control validation methods by reducing the likelihood that routing attacks can result in fraudulently issued certificates. Rather than performing domain control validation and authorization from a single geographic or routing vantage point, which an adversary could influence as demonstrated by security researchers, MPIC implementations perform the same validation from multiple geographic locations and/or Internet Service Providers. This has been observed as an effective countermeasure against ethically conducted, real-world BGP hijacks.

The Chrome Root Program led a work team of ecosystem participants, which culminated in a CA/Browser Forum Ballot to require adoption of MPIC via Ballot SC-067. The ballot received unanimous support from organizations who participated in voting. Beginning March 15, 2025, CAs issuing publicly-trusted certificates must now rely on MPIC as part of their certificate issuance process. Some of these CAs are relying on the Open MPIC Project to ensure their implementations are robust and consistent with ecosystem expectations.

We’d especially like to thank Henry Birge-Lee, Grace Cimaszewski, Liang Wang, Cyrill Krähenbühl, Mihir Kshirsagar, Prateek Mittal, Jennifer Rexford, and others from Princeton University for their sustained efforts in promoting meaningful web security improvements and ongoing partnership.

Linting

Linting refers to the automated process of analyzing X.509 certificates to detect and prevent errors, inconsistencies, and non-compliance with requirements and industry standards. Linting ensures certificates are well-formatted and include the necessary data for their intended use, such as website authentication.

Linting can expose the use of weak or obsolete cryptographic algorithms and other known insecure practices, improving overall security. Linting improves interoperability and helps CAs reduce the risk of non-compliance with industry standards (e.g., CA/Browser Forum TLS Baseline Requirements). Non-compliance can result in certificates being "mis-issued". Detecting these issues before a certificate is in use by a site operator reduces the negative impact associated with having to correct a mis-issued certificate.

There are numerous open-source linting projects in existence (e.g., certlint, pkilint, x509lint, and zlint), in addition to numerous custom linting projects maintained by members of the Web PKI ecosystem. “Meta” linters, like pkimetal, combine multiple linting tools into a single solution, offering simplicity and significant performance improvements to implementers compared to implementing multiple standalone linting solutions.

Last spring, the Chrome Root Program led ecosystem-wide experiments, emphasizing the need for linting adoption due to the discovery of widespread certificate mis-issuance. We later participated in drafting CA/Browser Forum Ballot SC-075 to require adoption of certificate linting. The ballot received unanimous support from organizations who participated in voting. Beginning March 15, 2025, CAs issuing publicly-trusted certificates must now rely on linting as part of their certificate issuance process.

What’s next?

We recently landed an updated version of the Chrome Root Program Policy that further aligns with the goals outlined in “Moving Forward, Together.” The Chrome Root Program remains committed to proactive advancement of the Web PKI. This commitment was recently realized in practice through our proposal to sunset demonstrated weak domain control validation methods permitted by the CA/Browser Forum TLS Baseline Requirements. The weak validation methods in question are now prohibited beginning July 15, 2025.

It’s essential we all work together to continually improve the Web PKI, and reduce the opportunities for risk and abuse before measurable harm can be realized. We continue to value collaboration with web security professionals and the members of the CA/Browser Forum to realize a safer Internet. Looking forward, we’re excited to explore a reimagined Web PKI and Chrome Root Program with even stronger security assurances for the web as we navigate the transition to post-quantum cryptography. We’ll have more to say about quantum-resistant PKI later this year.