Elie Bursztein, Cybersecurity & AI Research Director, and Marina Zhang, Software Engineer

Systems such as Gmail, YouTube and Google Play rely on text classification models to identify harmful content including phishing attacks, inappropriate comments, and scams. These types of texts are harder for machine learning models to classify because bad actors rely on adversarial text manipulations to actively attempt to evade the classifiers. For example, they will use homoglyphs, invisible characters, and keyword stuffing to bypass defenses. 

To help make text classifiers more robust and efficient, we’ve developed a novel, multilingual text vectorizer called RETVec (Resilient & Efficient Text Vectorizer) that helps models achieve state-of-the-art classification performance and drastically reduces computational cost. Today, we’re sharing how RETVec has been used to help protect Gmail inboxes.

Strengthening the Gmail Spam Classifier with RETVec

Figure 1. RETVec-based Gmail Spam filter improvements.

Over the past year, we battle-tested RETVec extensively inside Google to evaluate its usefulness and found it to be highly effective for security and anti-abuse applications. In particular, replacing the Gmail spam classifier’s previous text vectorizer with RETVec allowed us to improve the spam detection rate over the baseline by 38% and reduce the false positive rate by 19.4%. Additionally, using RETVec reduced the TPU usage of the model by 83%, making the RETVec deployment one of the largest defense upgrades in recent years. RETVec achieves these improvements by sporting a very lightweight word embedding model (~200k parameters), allowing us to reduce the Transformer model’s size at equal or better performance, and having the ability to split the computation between the host and TPU in a network and memory efficient manner.

RETVec Benefits

RETVec achieves these improvements by combining a novel, highly-compact character encoder, an augmentation-driven training regime, and the use of metric learning. The architecture details and benchmark evaluations are available in our NeurIPS 2023 paper and we open-source RETVec on Github.

Due to its novel architecture, RETVec works out-of-the-box on every language and all UTF-8 characters without the need for text preprocessing, making it the ideal candidate for on-device, web, and large-scale text classification deployments. Models trained with RETVec exhibit faster inference speed due to its compact representation. Having smaller models reduces computational costs and decreases latency, which is critical for large-scale applications and on-device models.

Figure 1. RETVec architecture diagram.

Models trained with RETVec can be seamlessly converted to TFLite for mobile and edge devices, as a result of a native implementation in TensorFlow Text. For web application model deployment, we provide a TensorflowJS layer implementation that is available on Github and you can check out a demo web page running a RETVec-based model.

Figure 2.  Typo resilience of text classification models trained from scratch using different vectorizers.

RETVec is a novel open-source text vectorizer that allows you to build more resilient and efficient server-side and on-device text classifiers. The Gmail spam filter uses it to help protect Gmail inboxes against malicious emails.

If you would like to use RETVec for your own use cases or research, we created a tutorial to help you get started.

This research was conducted by Elie Bursztein, Marina Zhang, Owen Vallis, Xinyu Jia, and Alexey Kurakin. We would like to thank Gengxin Miao, Brunno Attorre, Venkat Sreepati, Lidor Avigad, Dan Givol, Rishabh Seth and Melvin Montenegro and all the Googlers who contributed to the project.

Royal Hansen, Vice President of Privacy, Safety and Security Engineering, Google

Nearly half of third-parties fail to meet two or more of the Minimum Viable Secure Product controls. Why is this a problem? Because "98% of organizations have a relationship with at least one third-party that has experienced a breach in the last 2 years."

In this post, we're excited to share the latest improvements to the Minimum Viable Secure Product (MVSP) controls. We'll also shed light on how adoption of MVSP has helped Google improve its security processes, and hope this example will help motivate third-parties to increase their adoption of MVSP controls and thus improve product security across the industry.

About MVSP

In October 2021, Google publicly launched MVSP alongside launch partners. Our original goal remains unchanged: to provide a vendor-neutral application security baseline, designed to eliminate overhead, complexity, and confusion in the end-to-end process of onboarding third-party products and services. It covers themes such as procurement, security assessment, and contract negotiation.

Improvements since launch

As part of MVSP’s annual control review, and our core philosophy of evolution over revolution, the working group sought input from the broader security community to ensure MVSP maintains a balance between security and achievability.

As a result of these discussions, we launched updated controls. Key changes include: expanded guidance around external vulnerability reporting to protect bug hunters, and discouraging additional costs for access to basic security features – inline with CISA’s "Secure-by-Design" principles.

In 2022, we developed guidance on build process security based on SLSA, to reflect the importance of supply chain security and integrity.

From an organizational perspective, in the two years since launching, we've seen the community around MVSP continue to expand. The working group has grown to over 20 global members, helping to diversify voices and broaden expertise. We've also had the opportunity to present and discuss the program with a number of key groups, including an invitation to present at the United Nations International Computing Centre – Common Secure Conference.

Google at the UNICC conference in Valencia, Spain

How Google uses MVSP

Since its inception, Google has looked to integrate improvements to our own processes using MVSP as a template. Two years later, we can clearly see the impact through faster procurement processes, streamlined contract negotiations, and improved data-driven decision making.

Highlights

• After implementing MVSP into key areas of Google's third-party life-cycle, we've observed a 68% reduction in the time required for third-parties to complete assessment process.

• By embedding MVSP into select procurement processes, Google has increased data-driven decision making in earlier phases of the cycle.

• Aligning our Information Protection Addendum’s safeguards with MVSP has significantly improved our third-party privacy and security risk management processes.

You use MVSP to enhance your software or procurement processes by reviewing some common use-cases and adopting them into your third-party risk management and/or contracting workflows .

What's next?

We're invested in helping the industry manage risk posture through continuous improvement, while increasing the minimum bar for product security across the industry.

By making MVSP available to the wider industry, we are helping to create a solid foundation for growing the maturity level of products and services. Google has benefited from driving security and safety improvements through the use of leveled sets of requirements. We expect the same to be true across the wider industry.

We've seen success, but there is still work to be done. Based on initial observations, as mentioned above, 48% of third-parties fail to meet two or more of the Minimum Viable Secure Product controls.

As an industry, we can't stand still when it comes to product security. Help us raise the minimum bar for application security by adopting MVSP and ensuring we as an industry don’t accept anything less than a strong security baseline that works for the wider industry.

Acknowledgements

Google and the MVSP working group would like to thank those who have supported and contributed since its inception. If you'd like to get involved or provide feedback, please reach out.

Thank you to Chris John Riley, Gabor Acs-Kurucz, Michele Chubirka, Anna Hupa, Dirk Göhmann and Kaan Kivilcim from the Google MVSP Group for their contributions to this post.

Posted by Nataliya Stanetsky, Android Security and Privacy Team

The App Defense Alliance (ADA), an industry-leading collaboration launched by Google in 2019 dedicated to ensuring the safety of the app ecosystem, is taking a major step forward. We are proud to announce that the App Defense Alliance is moving under the umbrella of the Linux Foundation, with Meta, Microsoft, and Google as founding steering members.

This strategic migration represents a pivotal moment in the Alliance’s journey, signifying a shared commitment by the members to strengthen app security and related standards across ecosystems. This evolution of the App Defense Alliance will enable us to foster more collaborative implementation of industry standards for app security.

Uniting for App Security

The digital landscape is continually evolving, and so are the threats to user security. With the ever-increasing complexity of mobile apps and the growing importance of data protection, now is the perfect time for this transition. The Linux Foundation is renowned for its dedication to fostering open-source projects that drive innovation, security, and sustainability. By combining forces with additional members under the Linux Foundation, we can adapt and respond more effectively to emerging challenges.

The commitment of the newly structured App Defense Alliance’s founding steering members – Meta, Microsoft, and Google – is pivotal in making this transition a reality. With a member community spanning an additional 16 General and Contributor Members, the Alliance will support industry-wide adoption of app security best practices and guidelines, as well as countermeasures against emerging security risks.

Continuing the Malware Mitigation Program

The App Defense Alliance was formed with the mission of reducing the risk of app-based malware and better protecting Android users. Malware defense remains an important focus for Google and Android, and we will continue to partner closely with the Malware Mitigation Program members – ESET, Lookout, McAfee, Trend Micro, Zimperium – on direct signal sharing. The migration of ADA under the Linux Foundation will enable broader threat intelligence sharing across leading ecosystem partners and researchers.

Looking Ahead and Connecting With the ADA

We invite you to stay connected with the newly structured App Defense Alliance under the Linux foundation umbrella. Join the conversation to help make apps more secure. Together with the steering committee, alliance partners, and the broader ecosystem, we look forward to building more secure and trustworthy app ecosystems.

Posted by Andy Qin, Irene Ang, Kostya Serebryany, Evgenii Stepanov

Since 2018, Google has partnered with ARM and collaborated with many ecosystem partners (SoCs vendors, mobile phone OEMs, etc.) to develop Memory Tagging Extension (MTE) technology. We are now happy to share the growing adoption in the ecosystem. MTE is now available on some OEM devices (as noted in a recent blog post by Project Zero) with Android 14 as a developer option, enabling developers to use MTE to discover memory safety issues in their application easily.

The security landscape is changing dynamically, new attacks are becoming more complex and costly to mitigate. It’s becoming increasingly important to detect and prevent security vulnerabilities early in the software development cycle and also have the capability to mitigate the security attacks at the first moment of exploitation in production.

The biggest contributor to security vulnerabilities are memory safety related defects and Google has invested in a set of technologies to help mitigate memory safety risks. These include but are not limited to:

• Shifting to memory safe languages such as Rust as a proactive solution to prevent the new memory safety bugs from being introduced in the first place.
• Tools for detecting memory safety defects in the development stages and production environment, such as widely used sanitizer technologies¹ (ASAN, HWASAN, GWP-ASAN, etc.) as well as fuzzing (with sanitizers enabled).
• Foundational technologies like MTE, which many experts believe is the most promising path forward for improving C/C++ software security and it can be deployed both in development and production at reasonably low cost.

MTE is a hardware based capability that can detect unknown memory safety vulnerabilities in testing and/or mitigate them in production. It works by tagging the pointers and memory regions and comparing the tags to identify mismatches (details). In addition to the security benefits, MTE can also help ensure integrity because memory safety bugs remain one of the major contributors to silent data corruption that not only impact customer trust, but also cause lost productivity for software developers.

At the moment, MTE is supported on some of the latest chipsets:

• Focusing on security for Android devices, the MediaTek Dimensity 9300 integrates support for MTE via ARM's latest v9 architecture (which is what Cortex-X4 and Cortex-A720 processors are based on). This feature can be switched on and off in the bootloader by users and developers instead of having it always on or always off.
• Tensor G3 integrates support for MTE only within the developer mode toggle. Feature can be activated by developers.

For both chipsets, this feature can be switched on and off by developers, making it easier to find memory-related bugs during development and after deployment. MTE can help users stay safe while also improving time to market for OEMs.

Application developers will be the first to leverage this feature as a way to improve their application security and reliability in the software development lifecycle. MTE can effectively help them to discover hard-to-detect memory safety vulnerabilities (buffer overflows, user-after-free, etc.) with clear & actionable stack trace information in integration testing or pre-production environments. Another benefit of MTE is that the engineering cost of memory-safety testing is drastically reduced because heap bug detection (which is majority of all memory safety bugs) does not require any source or binary changes to leverage MTE, i.e. advanced memory-safety can be achieved with just a simple environment or configuration change.

We believe that MTE will play a very important role in detecting and preventing memory safety vulnerabilities and provide a promising path towards improving software security.

Notes

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1. ASAN = Address Sanitizer; HWASAN = HW based ASAN;GWP-ASAN = sampling based ASAN ↩

Posted by Chrome Security team

Improving the interoperability of web services is an important and worthy goal. We believe that it should be easier for people to maintain and control their digital identities. And we appreciate that policymakers working on European Union digital certificate legislation, known as eIDAS, are working toward this goal. However, a specific part of the legislation, Article 45, hinders browsers’ ability to enforce certain security requirements on certificates, potentially holding back advances in web security for decades. We and many past and present leaders in the international web community have significant concerns about Article 45's impact on security.

We urge lawmakers to heed the calls of scientists and security experts to revise this part of the legislation rather than erode users’ privacy and security on the web.

Posted by Nataliya Stanetsky, Android Security and Privacy Team

Keeping Google Play safe for users and developers remains a top priority for Google. As users increasingly prioritize their digital privacy and security, we continue to invest in our Data Safety section and transparency labeling efforts to help users make more informed choices about the apps they use.

Research shows that transparent security labeling plays a crucial role in consumer risk perception, building trust, and influencing product purchasing decisions. We believe the same principles apply for labeling and badging in the Google Play store. The transparency of an app’s data security and privacy play a key role in a user’s decision to download, trust, and use an app.

Highlighting Independently Security Tested VPN Apps

Last year, App Defense Alliance (ADA) introduced MASA (Mobile App Security Assessment), which allows developers to have their apps independently validated against a global security standard. This signals to users that an independent third-party has validated that the developers designed their apps to meet these industry mobile security and privacy minimum best practices and the developers are going the extra mile to identify and mitigate vulnerabilities. This, in turn, makes it harder for attackers to reach users' devices and improves app quality across the ecosystem. Upon completion of the successful validation, Google Play gives developers the option to declare an “Independent security review” badge in its Data Safety section, as shown in the image below. While certification to baseline security standards does not imply that a product is free of vulnerabilities, the badge associated with these validated apps helps users see at-a-glance that a developer has prioritized security and privacy practices and committed to user safety.

To help give users a simplified view of which apps have undergone an independent security validation, we’re introducing a new Google Play store banner for specific app types, starting with VPN apps. We’ve launched this banner beginning with VPN apps due to the sensitive and significant amount of user data these apps handle. When a user searches for VPN apps, they will now see a banner at the top of Google Play that educates them about the “Independent security review” badge in the Data Safety Section. Users also have the ability to “Learn More”, which redirects them to the App Validation Directory, a centralized place to view all VPN apps that have been independently security reviewed. Users can also discover additional technical assessment details in the App Validation Directory, helping them to make more informed decisions about what VPN apps to download, use, and trust with their data.

VPN providers such as NordVPN, Google One, ExpressVPN, and others have already undergone independent security testing and publicly declared the badge showing their good standing with the MASA program. We encourage and anticipate additional VPN app developers to undergo independent security testing, bringing even more transparency to users. If you are a VPN developer and interested in learning more about this feature, please submit this form.

Our Commitment to App Security and Privacy Transparency on Google Play

By encouraging independent security testing and displaying security badges for validated apps, we highlight developers who prioritize user safety and data transparency. We also provide developers with app security and privacy best practices – through Play PolicyBytes videos, webinars, blog posts, the Developer Help Community, and other resources – in accordance with our developer policies that help keep Google Play safe. We are continually working on improvements to our app review process, policies, and programs to keep users safe and to help developers navigate our policies with ease. To learn more about how we give developers the tools to succeed while keeping users safe on Google Play, read the Google Safety Center article.

Our efforts to prioritize security and privacy transparency on Google Play are aligned with the needs and expectations we’ve heard from both users and developers. We believe that by prioritizing initiatives that bolster user safety and trust, we can foster a thriving app ecosystem where users can make more informed app decisions and developers are encouraged to uphold the highest standards of security and privacy.