Google has unveiled a major security feature for Pixel owners, giving them the ability to verify the authenticity of their Pixel’s Android operating system.

Software supply chain attacks are designed to hide their presence from the user. As a result, users may unwittingly run a phone with a compromised OS, giving bad actors unfettered access to their information. Google is making it easier for users to be sure their devices have not been hacked, and their OS is intact with Pixel Binary Transparency.

Software Engineer Jay Hou described the feature in a company blog post:

Pixel Binary Transparency responds to a new wave of attacks targeting the software supply chain—that is, attacks on software while in transit to users. These attacks are on the rise in recent years, likely in part because of the enormous impact they can have. In recent years, tens of thousands of software users from Fortune 500 companies to branches of the US government have been affected by supply chain attacks that targeted the systems that create software to install a backdoor into the code, allowing attackers to access and steal customer data.

One way Google protects against these types of attacks is by auditing Pixel phone firmware (also called “factory images”) before release, during which the software is thoroughly checked for backdoors. Upon boot, Android Verified Boot runs a check on your device to be sure that it’s still running the audited code that was officially released by Google. Pixel Binary Transparency now expands on that function, allowing you to personally confirm that the image running on your device is the official factory image—meaning that attackers haven’t inserted themselves somewhere in the source code, build process, or release aspects of the software supply chain. Additionally, this means that even if a signing key were compromised, binary transparency would flag the unofficially signed images, deterring attackers by making their compromises more detectable.

Google says many users won’t need to use all the features involved in Pixel Binary Transparency, but the ability is there for those that need/want it:

Most Pixel owners won’t ever need to perform the consistency and inclusion proofs to check their Pixel’s image—Android Verified Boot already has multiple safeguards in place, including verifying the hash of the code and data contents and checking the validity of the cryptographic signature. However, we’ve made the process available to anyone who wants to check themselves—the Pixel Binary Transparency Log Technical Detail Page will walk you through extracting the metadata from your phone and then running the inclusion and consistency proofs to compare against the log.