Patch Levels

A note on operating system security

There is a singular all-or-nothing, all-encompassing Android security bulletin released every month that covers security issues across the entire system. Below we break it into five parts solely for ease of understanding for you to determine the general security of a given operating system. Being behind on any one part means the system is inherently insecure.

1. the version of Android itself, newer versions have more security features/hardening
2. the ASB patch level, these are essential security patches
3. the Pixel ASB patch level, these are recommended security patches and are only provided for the latest Android version. Despite the name, the majority are NOT Pixel specific as described here and here.
4. the vendor (aka SOC) ASB patch level, see e.g. Qualcomm
5. and lastly the Linux kernel version, newer versions have more security features/hardening

Does AXP.OS make my device secure?

The short answer: No. “Just” more secure.

The long answer is that AXP.OS is likely the best harm reduction option if your device is no longer in support by its manufacturer or vendor. Any project or product claiming they make end-of-life devices secure should be rigorously scrutinized.

AXP.OS tries to fill a gap mainly for end-of-life devices and offers more security and privacy than e.g. an outdated STOCK OS version of such a device. Compared to other custom OS it even offers highly increased security due to the integrated kernel patching (see The AXP.OS patch level)

Lastly it must be noted that privacy and security go hand-in-hand, there is a fundamental limit of how much privacy you can achieve if you do not have security backing it up.

If AXP.OS isn’t secure, then why should I be using it?

To be clear: you should seek out a newer non-EOL device, but not everyone can afford such.

Additionally for a handful of use cases AXP.OS fills the gap enough to be OKish, eg. offline music/maps/wikipedia device, basic gaming (solitaire/sudoku/etc.), basic browsing of trusted websites with updated browsers, a spare/backup device, website or Android app development/testing, etc.

And security aside, it still has substantial benefits over the stock/final release for EOL devices.

The AXP.OS patch level

Each month Google releases an Android Security Bulletin (“ASB”) which contains important patches and marked with 2 different patch dates (details).