CVE-2026-80627 MIPS: mm: Fix out-of-bounds write in maar_res_walk()
An out-of-bounds write in the MIPS memory management code allows local attackers to potentially execute arbitrary code or escalate privileges.
- 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-2026-80627?
CVE-2026-80627 is a memory corruption vulnerability in Linux, published on 28 Aug 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:
MIPS: mm: Fix out-of-bounds write in maar_res_walk()
maar_res_walk() uses wi->num_cfg as the index into the fixed-size wi->cfg array, but checks whether the array is full only after it has filled the selected entry. If walk_system_ram_range() reports more than 16 memory ranges, the overflow call writes one struct maar_config past the end of the array before WARN_ON() prevents num_cfg from advancing.
Move the full-array check before taking the array slot and return non-zero when the scratch array is full, so walk_system_ram_range() terminates the walk instead of invoking the callback for further ranges.
Which versions are affected by CVE-2026-80627?
How do I fix CVE-2026-80627?
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-2026-80627 being exploited?
There is no known exploitation of CVE-2026-80627 in the wild and no public exploit code.
Sources
Also known as BELL-CVE-2026-80627, DEBIAN-CVE-2026-80627, GHSA-52jh-gf9j-c2mq, UBUNTU-CVE-2026-80627.