CVE-2025-68317 io_uring/zctx: check chained notif contexts
The Linux kernel io_uring zero-copy notification context check was added to prevent potential issues in chained notification handling.
- 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-2025-68317?
CVE-2025-68317 is a high-severity vulnerability in Linux, published on 16 Dec 2025. 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/zctx: check chained notif contexts
Send zc only links ubuf_info for requests coming from the same context. There are some ambiguous syz reports, so let's check the assumption on notification completion.
Which versions are affected by CVE-2025-68317?
How do I fix CVE-2025-68317?
Apply the vendor's patch.
Is CVE-2025-68317 being exploited?
There is no known exploitation of CVE-2025-68317 in the wild and no public exploit code.
Sources
Also known as BELL-CVE-2025-68317, DEBIAN-CVE-2025-68317, GHSA-7p3q-9c8m-84x3, ROOT-OS-UBUNTU-2204-CVE-2025-68317, ROOT-OS-UBUNTU-2404-CVE-2025-68317, UBUNTU-CVE-2025-68317.