CVE-2026-74258 bpf: Guard __get_user acesss with access_ok for uprobe_multi data
Missing access_ok check in Linux kernel BPF uprobe_multi allows unauthorized user-space memory access, potentially leading to privilege escalation or data leaks.
- 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-2026-74258?
CVE-2026-74258 is a high-severity missing authorization vulnerability in Linux, published on 15 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:
bpf: Guard __get_user acesss with access_ok for uprobe_multi data
As reported by sashiko [1] we need to use access_ok to check the user space data bounds before we use __get-user to get it.
[1] https://lore.kernel.org/bpf/20260610145235.CB1441F00893@smtp.kernel.org/
Which versions are affected by CVE-2026-74258?
How do I fix CVE-2026-74258?
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-2026-74258 being exploited?
There is no known exploitation of CVE-2026-74258 in the wild and no public exploit code.
Sources
Also known as AZL-96552, BELL-CVE-2026-74258, DEBIAN-CVE-2026-74258, GHSA-pwvf-7f5w-2qr5, UBUNTU-CVE-2026-74258.