CVE-2026-31416 netfilter: nfnetlink_log: account for netlink header size
A missing header size calculation in the Linux kernel netfilter module can cause message drops and warnings, potentially leading to denial of service.
- 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-2026-31416?
CVE-2026-31416 is a medium-severity denial of service vulnerability in Linux kernel, published on 13 Apr 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:
netfilter: nfnetlink_log: account for netlink header size
This is a followup to an old bug fix: NLMSG_DONE needs to account for the netlink header size, not just the attribute size.
This can result in a WARN splat + drop of the netlink message, but other than this there are no ill effects.
Which versions are affected by CVE-2026-31416?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2026-31416?
Apply the vendor's patch.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2026-31416 being exploited?
There is no known exploitation of CVE-2026-31416 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as AZL-82691, BELL-CVE-2026-31416, DEBIAN-CVE-2026-31416, GHSA-9rm5-vvv7-3j2x, ROOT-OS-DEBIAN-11-CVE-2026-31416, ROOT-OS-DEBIAN-12-CVE-2026-31416 and 4 more.