CVE-2026-45995 io_uring/zcrx: fix user_struct uaf
A use-after-free vulnerability in the Linux kernel's io_uring subsystem allows local attackers to potentially escalate privileges or execute code.
- 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-2026-45995?
CVE-2026-45995 is a high-severity use after free vulnerability in Linux kernel, published on 27 May 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:
io_uring/zcrx: fix user_struct uaf
io_free_rbuf_ring() usees a struct user_struct, which io_zcrx_ifq_free() puts it down before destroying the ring.
Weakness: CWE-416
Which versions are affected by CVE-2026-45995?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2026-45995?
Apply the vendor's patch.
Upgrade to the fixed version. These bugs are found with fuzzing and sanitisers and avoided by memory-safe languages. More about Use after free.
Is CVE-2026-45995 being exploited?
There is no known exploitation of CVE-2026-45995 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as DEBIAN-CVE-2026-45995, GHSA-33gx-9hw6-qc5v, UBUNTU-CVE-2026-45995.