NULL pointer dereference in Linux kernel - CVE-2026-45842
Published: May 28, 2026
Vulnerability identifier: #VU132658
CSH Severity: Low
CVSS v4.0: 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/E:U/U:Clear
CVE-ID: CVE-2026-45842
CWE-ID: CWE-476
Exploitation vector: Local access
Exploit availability:
No public exploit available
Vendor: Linux Foundation
Affected software:
Linux kernel
Linux kernel
Detailed vulnerability description
The vulnerability allows a local user to cause a denial of service.
The vulnerability exists due to a null pointer dereference in the SLIP/PPP VJ receive handling code when processing inbound VJ-compressed or VJ-uncompressed frames after installing a malformed VJ state with zero receive slots. A local user can configure PPP compression state through /dev/ppp and trigger processing of a frame selecting slot 0 to cause a denial of service.
The issue is reachable through PPPIOCSMAXCID from an unprivileged user namespace.
How to mitigate CVE-2026-45842
Install security update from vendor's repository.
Sources
- https://git.kernel.org/stable/c/7b0d9e878ec2b21d99ae8051b3dda59cdb66c152
- https://git.kernel.org/stable/c/9e1ff0eead073c4f46d874ad2526b7dda5465faf
- https://git.kernel.org/stable/c/c6980e8b1a86288167f34966fa5219031999b6f1
- https://git.kernel.org/stable/c/de42f86e2cf5028a97e74c25869d1a962b13c301
- https://git.kernel.org/stable/c/e76607442d5b73e1ba6768f501ef815bb58c2c0e