GrapheneOS may skip Pixel 11 support over missing ARM memory tagging hardware

GrapheneOS hits a wall porting to Pixel 11

GrapheneOS, the security- and privacy-focused Android distribution, says it may never support Google's Pixel 11 series after roughly a week of porting work revealed that the new phones appear to ship without usable support for ARM's Memory Tagging Extension (MTE). According to Cyber Insider, the project disclosed the problem in a post on X dated August 29, stating that MTE is missing at the software and firmware levels and is, in its assessment, almost certainly absent from the silicon itself. Without it, the team says it cannot complete the port to the security standard it holds itself to.

What MTE does and why GrapheneOS depends on it

MTE is an ARM hardware feature that tags memory allocations so that invalid or unexpected memory accesses can be detected before an attacker turns them into an exploit. GrapheneOS has leaned on it heavily since the Pixel 8 introduced support in October 2023, applying hardware tagging across the kernel, its hardened_malloc allocator, and standard system processes.

The scenario the project is most concerned about is the After First Unlock (AFU) state — the period after a user has unlocked the phone at least once. In GrapheneOS's view, losing MTE would substantially weaken its defenses against both remote and local memory-corruption attacks in that state.

No explanation from Google

Cyber Insider reports that Google has not given GrapheneOS an explanation for the apparent removal. The project believes cost-cutting is the most likely motivation, though it acknowledged that an undisclosed hardware flaw could be another possibility. It also said it had previously heard from a Google insider that MTE might be dropped from a future Pixel generation.

Pixel 11 security gains don't offset the loss

The Pixel 11 is not without security improvements. GrapheneOS itself highlighted post-quantum ML-DSA signatures for verified boot, the replacement of Samsung's Shannon IMS components with AOSP IMS, and the new Titan M3 security chip, which the project expects to better resist data extraction while a phone sits in the Before First Unlock state.

Even so, the project argues those additions do not compensate for losing MTE. It currently recommends the Pixel 8, Pixel 9 and Pixel 10 as better overall devices for running GrapheneOS, and for anyone who bought a Pixel 11 specifically to install the OS, its advice is to return the handset if that is still an option.

A push away from Google hardware

The discovery could also speed up GrapheneOS's drift away from Pixel devices. As Cyber Insider notes, Pixels stopped serving as Android Open Source Project reference devices with Android 16, which has made supporting them more difficult. The team is now weighing skipping the Pixel 11 generation entirely and redirecting development effort toward its upcoming Motorola partnership. A Motorola flagship expected in 2027 is planned to meet the project's hardware security requirements, including MTE support.

Why it matters

For GrapheneOS users, this is an immediate practical decision: the newest Pixels may never run the OS, and buyers are being steered toward the Pixel 8 through Pixel 10 line instead. The broader signal is that hardware-backed memory safety features are not guaranteed to survive from one device generation to the next, and their quiet removal weakens real defenses against memory-corruption exploits. It also shows how much leverage hardware vendors hold over custom Android builds — as Pixels retreat from their reference role in AOSP, third-party secure OS projects must line up new hardware partners to keep existing at all.