CVE-2026-63954 hpfs: fix a crash if hpfs_map_dnode_bitmap fails
A local attacker can cause a system crash by triggering a null pointer dereference in the HPFS filesystem driver when bitmap mapping fails.
- 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-2026-63954?
CVE-2026-63954 is a high-severity vulnerability in Linux, published on 19 Jul 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:
hpfs: fix a crash if hpfs_map_dnode_bitmap fails
If hpfs_map_dnode_bitmap fails, the code would call hpfs_brelse4 on uninitialized quad buffer head, causing a crash.
Which versions are affected by CVE-2026-63954?
How do I fix CVE-2026-63954?
Apply the vendor's patch.
Is CVE-2026-63954 being exploited?
There is no known exploitation of CVE-2026-63954 in the wild and no public exploit code.
Sources
Also known as AZL-92757, BELL-CVE-2026-63954, DEBIAN-CVE-2026-63954, GHSA-67c6-765v-26g2, ROOT-OS-UBUNTU-2204-CVE-2026-63954, UBUNTU-CVE-2026-63954.