CVE-2026-80865 bpf: Add missing access_ok call to copy_user_syms
A missing access_ok check in the Linux kernel BPF subsystem allows local attackers to read arbitrary kernel memory or escalate privileges.
- 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-2026-80865?
CVE-2026-80865 is a missing authorization vulnerability in Linux, published on 4 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: Add missing access_ok call to copy_user_syms
As reported by sashiko we use __get_user without prior access_ok call on the user space pointer. Adding the missing call for the whole pointer array.
Plus removing the err check in the error path, because it's not needed and also we can return -ENOMEM directly from the first kvmalloc_array fail path.
[1] https://lore.kernel.org/bpf/[email protected]/
Which versions are affected by CVE-2026-80865?
How do I fix CVE-2026-80865?
Apply the vendor's patch.
Upgrade, and check permissions on every request on the server, not only in the interface. More about Missing authorization.
Is CVE-2026-80865 being exploited?
There is no known exploitation of CVE-2026-80865 in the wild and no public exploit code.
Sources
Also known as BELL-CVE-2026-80865, DEBIAN-CVE-2026-80865, GHSA-jrm7-h4fx-vpxv, UBUNTU-CVE-2026-80865.