NULL pointer dereference in Linux kernel - CVE-2026-72034
Published: August 16, 2026
Vulnerability identifier: #VU143557
CSH Severity: Low
CVSS v4: 5.6 [CVSS:4.0/AV:L/AC:L/AT:P/PR:H/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-72034
CWE-ID: CWE-476
Exploitation vector: Local access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a local privileged user to cause a denial of service.
The vulnerability exists due to a null pointer dereference in capable_wrt_mount() when handling open_by_handle_at() on a detached mount during a race condition. A local privileged user can trigger the race using open_tree(..., OPEN_TREE_CLONE) and open_by_handle_at() to cause a denial of service.
The issue occurs when a detached mount is dissolved while open_by_handle_at() is between mount state checks, causing mount->mnt_ns to become NULL.
Affected software
Linux kernel
How to mitigate CVE-2026-72034
Install security update from vendor's repository.
Linux kernel - update to 7.0 rc3