CVE-2026-89954 mtd: afs: validate v2 image info bounds
An attacker with flash access can trigger an integer overflow in the AFS v2 parser, potentially causing a kernel crash or arbitrary code execution.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-89954?
CVE-2026-89954 is a high-severity vulnerability in Linux, published on 16 Sep 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:
mtd: afs: validate v2 image info bounds
The AFS v2 parser uses footer[8] to locate the image information block inside the current erase block, then uses the image information region_count to walk entries from a fixed local array. The footer offset and region count come from flash contents and are not checked against the erase block or the local image-info array before use.
Reject v2 entries whose image information offset would underflow the erase block calculation, and reject region counts that cannot fit in the local image-info array before walking region entries.
Which versions are affected by CVE-2026-89954?
How do I fix CVE-2026-89954?
Apply the vendor's patch.
Is CVE-2026-89954 being exploited?
There is no known exploitation of CVE-2026-89954 in the wild and no public exploit code.
Sources
Also known as AZL-101358, BELL-CVE-2026-89954, DEBIAN-CVE-2026-89954, GHSA-jx3v-9v24-f367, UBUNTU-CVE-2026-89954.