NULL Pointer Dereference in Linux kernel - CVE-2026-23249
Published: March 20, 2026
Vulnerability details
The vulnerability allows a local user to cause a denial of service.
The vulnerability exists due to a null pointer dereference in the XFS filesystem's btree revalidation functionality when handling ioctl requests. A local user can trigger a specially crafted ioctl request to cause a null pointer dereference and crash the system.
The attacker must have privileges to perform XFS filesystem scrub operations, which typically requires administrative privileges.
Affected software
Debian Linux
Ubuntu
linux (Ubuntu package)
linux-azure-fips (Ubuntu package)
linux-hwe-6.8 (Ubuntu package)
linux-nvidia-tegra (Ubuntu package)
linux-aws-6.8 (Ubuntu package)
linux-raspi (Ubuntu package)
linux-azure-fde (Ubuntu package)
linux-azure-fde-6.8 (Ubuntu package)
linux-azure (Ubuntu package)
linux-raspi-realtime (Ubuntu package)
linux (Debian package)
How to mitigate CVE-2026-23249
linux (Ubuntu package) - addressed in versions 6.8.0-134.134, 6.8.0-1057.58~22.04.1, 6.8.0-1058.61+fips1, 6.8.0-1058.61~22.04.1, 6.8.0-1060.61, 6.8.0-1060.63+fips1, 6.8.0-1060.63~22.04.1, 6.8.0-1063.69, 6.8.0-1063.69+fips1, 6.8.1-1055.56, 6.8.1-1055.56~22.04.1
linux-azure-fips (Ubuntu package) - addressed in versions 6.8.0-134.134+fips1, 6.8.0-1062.69+fips1
linux-hwe-6.8 (Ubuntu package) - update to 6.8.0-136.136~22.04.1
linux-nvidia-tegra (Ubuntu package) - update to 6.8.0-1029.30
linux-aws-6.8 (Ubuntu package) - addressed in versions 6.8.0-1045.48, 6.8.0-1057.58~22.04.1, 6.8.0-1058.61.1, 6.8.0-1058.64, 6.8.0-1060.61~22.04.1, 6.8.0-1060.63~22.04.1, 6.8.0-1063.69~22.04.1
linux-raspi (Ubuntu package) - update to 6.8.0-1060.64
linux-azure-fde (Ubuntu package) - update to 6.8.0-1062.69
linux-azure-fde-6.8 (Ubuntu package) - update to 6.8.0-1062.69~22.04.1
linux-azure (Ubuntu package) - addressed in versions 6.8.0-1063.71, 6.8.0-1063.71~22.04.1
linux-raspi-realtime (Ubuntu package) - update to 6.8.0-2049.50
linux (Debian package) - update to 6.12.85-1
External References
Related Security Bulletins
- NULL Pointer Dereference in Linux kernel xfs scrub
- Debian update for linux
- Ubuntu update for linux
- Ubuntu update for linux-nvidia-tegra
- Ubuntu update for linux-aws-6.8
- Ubuntu update for linux-raspi-realtime
- Ubuntu update for linux-raspi
- Ubuntu update for linux-azure-fips
- Ubuntu update for linux-azure-fde-6.8
- Ubuntu update for linux-azure-fde
- Ubuntu update for linux-azure
- Ubuntu update for linux-hwe-6.8