CVE-2026-93112 bpf: Require a BPF cpumask for bpf_cpumask_populate()
A type confusion in the Linux kernel BPF subsystem allows writing to read-only memory, potentially enabling privilege escalation or code execution.
- 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-2026-93112?
CVE-2026-93112 is a high-severity memory corruption vulnerability in Linux, published on 17 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:
bpf: Require a BPF cpumask for bpf_cpumask_populate()
bpf_cpumask_populate() writes to its destination with bitmap_copy(), but the destination is typed as struct cpumask *. That allows the verifier to accept borrowed cpumask pointers returned by read-only kfuncs, such as scx_bpf_get_online_cpumask(), as a writable destination.
Make the destination a struct bpf_cpumask * so populate follows the same ownership rule as the other mutating cpumask kfuncs. Query kfuncs continue to accept const struct cpumask * inputs.
Which versions are affected by CVE-2026-93112?
How do I fix CVE-2026-93112?
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-2026-93112 being exploited?
There is no known exploitation of CVE-2026-93112 in the wild and no public exploit code.
Sources
Also known as BELL-CVE-2026-93112, DEBIAN-CVE-2026-93112, GHSA-8wvc-jp6j-85p4, UBUNTU-CVE-2026-93112.