NULL pointer dereference in Linux kernel - CVE-2026-72242
Published: August 16, 2026
Vulnerability identifier: #VU143348
CSH Severity: Low
CVSS v4: 6.8 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-72242
CWE-ID: CWE-476
Exploitation vector: Local access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a local user to cause a denial of service.
The vulnerability exists due to a NULL pointer dereference in selinux_sctp_bind_connect() when processing SCTP ASCONF operations from the softirq path. A local user can trigger the vulnerable SCTP bind or connect handling to cause a denial of service.
The issue occurs when the hook is invoked from the ASCONF softirq path, where no file reference guarantees that sk->sk_socket is non-NULL.
Affected software
Linux kernel
Ubuntu
linux-gcp-7.0 (Ubuntu package)
linux-azure-7.0 (Ubuntu package)
Ubuntu
linux-gcp-7.0 (Ubuntu package)
linux-azure-7.0 (Ubuntu package)
How to mitigate CVE-2026-72242
Install security update from vendor's repository.
Linux kernel - update to 7.0 rc3
linux-gcp-7.0 (Ubuntu package) - addressed in versions 7.0.0-38.38~24.04.4, 7.0.0-1013.13~24.04.1, 7.0.0-1014.14~24.04.1
linux-azure-7.0 (Ubuntu package) - addressed in versions 7.0.0-1016.16~24.04.1, 7.0.0-1017.17~24.04.1
linux-gcp-7.0 (Ubuntu package) - addressed in versions 7.0.0-38.38~24.04.4, 7.0.0-1013.13~24.04.1, 7.0.0-1014.14~24.04.1
linux-azure-7.0 (Ubuntu package) - addressed in versions 7.0.0-1016.16~24.04.1, 7.0.0-1017.17~24.04.1
External References
- https://git.kernel.org/stable/c/37d642b37ccdc31e1947c2ebc8dc38f03d4a0ceb
- https://git.kernel.org/stable/c/56acfeb10019e200ab6787d01f8d7cbe0f01526f
- https://git.kernel.org/stable/c/5d4d93f9bfbc997ffbb03cd6107e8f6979dbb9b4
- https://git.kernel.org/stable/c/cc8bd47b35eca82393cbad08b1cc86f02e034439
- https://git.kernel.org/stable/c/d61a80b17254be7230bc5544f8e62ddf21ab38e2