Android Security Bulletin (ASB) for October 2025 is empty:
https://source.android.com/docs/security/bulletin/2025-10-01
However, you can see Samsung has a list of ASB patches for their October 2025 release exclusive to flagships:
https://security.samsungmobile.com/securityUpdate.smsb
It's a small subset of the December 2025 patches.
Android now discloses patches around 3 months prior to their inclusion in a bulletin requiring them to raise the Android security patch level. However, OEMs are allowed to ship the patches as soon as they're receive. We're doing this in our security preview release, but with the full set of patches.
Our initial security preview release on September 25th with the November/December patches included 1 Critical severity patch and 54 High severity patches, which is the full subset applicable to Android 16. In the past couple days, 5 patches applicable to Android 16 were added and 1 was retracted.
December 2025 patches from the past couple days have been included and the January 2025 preview is now available.
Our next release coming today provides a choice to use our security preview releases in the initial setup wizard with a notification for existing users. Opting into it is recommended.
@bartavi @GrapheneOS I am using it primarily for being open source, secondarily for being secure. If GrapheneOS was closed source, I would be using a less secure, but open source OS instead. I might not be in the majority, but I'm definitely not alone.