CVE-2026-80675 libbpf: Reject non-exclusive metadata maps in the signed loader
A flaw in the Linux kernel's signed BPF loader allows bypassing integrity checks if map exclusivity is not enforced, potentially allowing stale data validation.
- 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-2026-80675?
CVE-2026-80675 is a high-severity 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:
libbpf: Reject non-exclusive metadata maps in the signed loader
The loader verifies map->sha against the metadata hash in its instructions. map->sha is calculated when BPF_OBJ_GET_INFO_BY_FD is called on the frozen map.
While the map is frozen, the /signed loader/ must also ensure the map is exclusive, as, without exclusivity (which a hostile host could just omit when loading the loader), another BPF program with map access can mutate the contents afterwards, so the check passes on stale data.
With the extra check as part of the signed loader, it now refuses to move on with map->sha validation if the host set it up wrongly.
Which versions are affected by CVE-2026-80675?
How do I fix CVE-2026-80675?
Apply the vendor's patch.
Is CVE-2026-80675 being exploited?
There is no known exploitation of CVE-2026-80675 in the wild and no public exploit code.
Sources
Also known as BELL-CVE-2026-80675, DEBIAN-CVE-2026-80675, GHSA-82gv-94cv-gr24, UBUNTU-CVE-2026-80675.