CVE-2026-98791 net/mlx5e: Fix AF_XDP TX timestamp teardown NULL dereference
A NULL pointer dereference in the Linux kernel mlx5e driver during AF_XDP teardown can cause a system crash, requiring local access and specific network configuration.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-98791?
CVE-2026-98791 is a vulnerability in Linux, published on 18 Oct 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:
net/mlx5e: Fix AF_XDP TX timestamp teardown NULL dereference
During XSK TX queue teardown, outstanding descriptors are completed without a CQE. If one requested a TX timestamp, the completion path passes that NULL CQE to mlx5e_xsk_fill_timestamp(), which dereferences it.
Return zero when no CQE is available, indicating that teardown did not produce a TX timestamp.
Which versions are affected by CVE-2026-98791?
How do I fix CVE-2026-98791?
Apply the vendor's patch.
Is CVE-2026-98791 being exploited?
There is no known exploitation of CVE-2026-98791 in the wild and no public exploit code.
Sources
Also known as BELL-CVE-2026-98791, DEBIAN-CVE-2026-98791, GHSA-5f42-c4x2-rx63, UBUNTU-CVE-2026-98791.