CVE-2026-23043 btrfs: fix NULL pointer dereference in do_abort_log_replay()
A local attacker can cause a kernel crash via a NULL pointer dereference in the btrfs filesystem log replay abort path.
- 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-2026-23043?
CVE-2026-23043 is a vulnerability in Linux, published on 4 Feb 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:
btrfs: fix NULL pointer dereference in do_abort_log_replay()
Coverity reported a NULL pointer dereference issue (CID 1666756) in do_abort_log_replay(). When btrfs_alloc_path() fails in replay_one_buffer(), wc->subvol_path is NULL, but btrfs_abort_log_replay() calls do_abort_log_replay() which unconditionally dereferences wc->subvol_path when attempting to print debug information. Fix this by adding a NULL check before dereferencing wc->subvol_path in do_abort_log_replay().
Which versions are affected by CVE-2026-23043?
How do I fix CVE-2026-23043?
Apply the vendor's patch.
Is CVE-2026-23043 being exploited?
There is no known exploitation of CVE-2026-23043 in the wild and no public exploit code.
Sources
Also known as BELL-CVE-2026-23043, DEBIAN-CVE-2026-23043, GHSA-79jf-89ph-wp26, UBUNTU-CVE-2026-23043.