CVE-2026-31690 firmware: thead: Fix buffer overflow and use standard endian macros
A buffer overflow in the TH1520 AON firmware protocol driver allows attackers to potentially execute arbitrary code or cause a system crash.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-31690?
CVE-2026-31690 is a high-severity memory corruption vulnerability in Linux kernel, published on 27 Apr 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
In the Linux kernel, the following vulnerability has been resolved:
firmware: thead: Fix buffer overflow and use standard endian macros
Addresses two issues in the TH1520 AON firmware protocol driver:
1. Fix a potential buffer overflow where the code used unsafe pointer arithmetic to access the 'mode' field through the 'resource' pointer with an offset. This was flagged by Smatch static checker as: "buffer overflow 'data' 2 <= 3"
2. Replace custom RPC_SET_BE* and RPC_GET_BE* macros with standard kernel endianness conversion macros (cpu_to_be16, etc.) for better portability and maintainability.
The functionality was re-tested with the GPU power-up sequence, confirming the GPU powers up correctly and the driver probes successfully.
[ 12.702370] powervr ffef400000.gpu: [drm] loaded firmware powervr/rogue_36.52.104.182_v1.fw [ 12.711043] powervr ffef400000.gpu: [drm] FW version v1.0 (build 6645434 OS) [ 12.719787] [drm] Initialized powervr 1.0.0 for ffef400000.gpu on minor 0
Weakness: CWE-787
Which versions are affected by CVE-2026-31690?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2026-31690?
Apply the vendor's patch.
Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.
Is CVE-2026-31690 being exploited?
There is no known exploitation of CVE-2026-31690 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as BELL-CVE-2026-31690, DEBIAN-CVE-2026-31690, GHSA-3j3v-v8vh-9mw9, UBUNTU-CVE-2026-31690.