This article covers a developing story. Continue to check back with us as we will be adding more information as it becomes available.
Google has started rolling out the May 2025 security patches to all eligible Pixel phones, tablets, and foldables, and the changelog is fairly minimal. But this one comes with a wrinkle — in order to block exploits from past versions, the bootloader has been updated with a new anti-rollback threshold. In other words, once you update to the May 2025 security patches, there’s no going back to older firmware versions.
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The company announced today’s update on its product forums, noting that it has a build number of BP1A.250505.005 on most eligible devices. The update is being seeded to all of Google’s Android devices starting today, from the Pixel 6 through the Pixel 9a, though the company notes that the rollout will be conducted in phases over the course of the next week.
Google’s release notes mention fixes for poor microphone quality in some apps, Bluetooth pairing with certain smartwatches, and a bug where the device’s secondary language was erroneously displayed in the Quick Settings.
The May 2025 update includes bug fixes and improvements for Pixel users – see below for details
- Fix for degraded microphone recording quality in certain apps
- Fix for Bluetooth pairing issues with certain smartwatches under certain conditions
- Fix for secondary language displayed in quick settings under certain conditions*
Unfortunately, there’s no mention of the delayed notifications bug that has been plaguing many Pixel users since the April 2025 update rolled out. We will have to test the new version for a day or two to see if this issue has been resolved.
Zero days and anti-rollback measures
On the factory images page for this new version, Google explains that today’s update “increments” the anti-rollback version for the bootloader. The bootloader is a piece of low-level software that loads the Android system images when your phone starts up — not very different from your PC’s BIOS or UEFI loading up Windows — so it can be used to define a minimum OS version. With this update, the minimum OS version threshold has been raised to May 2025.
The May 2025 update for Pixel 6 (6, 6 Pro, 6a) and Pixel 8 (8, 8 Pro, 8a) devices contains a bootloader update that increments the anti-roll back version for the bootloader. This prevents the device from rolling back to previous vulnerable versions of the bootloader. After flashing the May 2025 update on these devices you won’t be able to flash and boot older Android 15 builds.
You’ll notice that Google mentions “previous vulnerable versions” in its warning about the new anti-rollback threshold. The purpose of raising this threshold is to prevent a bad actor from being able to flash older firmware over top of this update, thus making it possible to exploit a recently-patched vulnerability again.
This article covers a developing story. Continue to check back with us as we will be adding more information as it becomes available.
