#VU124536 Incomplete Blacklist to Cross-Site Scripting in Linux kernel - CVE-2026-23321
Published: March 25, 2026
Vulnerability identifier: #VU124536
Vulnerability risk: Low
CVSSv4.0: 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-2026-23321
CWE-ID: CWE-692
Exploitation vector: Local access
Exploit availability:
No public exploit available
Vulnerable software:
Linux kernel
Linux kernel
Software vendor:
Linux Foundation
Linux Foundation
Description
The vulnerability allows a local user to cause a denial of service.
The vulnerability exists due to improper state management in the MPTCP subsystem when handling endpoint removal. A local user can send a specially crafted sequence of netlink commands to trigger a kernel warning and system instability.
The attacker must be able to create and remove MPTCP endpoints with specific flags and manipulate connection states, which requires access to the MPTCP netlink interface.
Remediation
Install security update from vendor's repository.
External links
- https://git.kernel.org/stable/c/05799c2f1ca5eb13d65764dda688d02021b65e06
- https://git.kernel.org/stable/c/198824ccfa64ffebd918bf99c939bd8170a4a4d8
- https://git.kernel.org/stable/c/579a752464a64cb5f9139102f0e6b90a1f595ceb
- https://git.kernel.org/stable/c/67f34ab318807989b57dfdb0f79e2d4e57018290
- https://git.kernel.org/stable/c/a64aa7db39392add5be09dffaedbf1f0ce5554df
- https://git.kernel.org/stable/c/c5c877e140e5f46023a74a51e577ce5edd0a4be7