Improper resource shutdown or release in Linux kernel - CVE-2026-46170

Vulnerability identifier: #VU133026

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-2026-46170

CWE-ID: CWE-404

Exploitation vector: Local access

Exploit availability: No public exploit available

The vulnerability allows a local user to cause a denial of service.

The vulnerability exists due to improper resource shutdown or release in the mptcp path manager ADD_ADDR retransmission timer handling when processing ADD_ADDR retransmissions. A local user can trigger ADD_ADDR retransmissions to cause a system hang.

The issue occurs when the last socket reference is released from the timer handler, leading to an indefinite wait on the same timer.

Linux kernel
Debian Linux
Ubuntu
linux (Debian package)
linux (Ubuntu package)
linux-ibm (Ubuntu package)
linux-oem-7.0 (Ubuntu package)
linux-azure (Ubuntu package)
linux-aws (Ubuntu package)

Install security update from vendor's repository.

linux (Debian package) - update to 6.12.94-1
linux (Ubuntu package) - addressed in versions 7.0.0-28.28, 7.0.0-28.28.1, 7.0.0-1003.4, 7.0.0-1008.8
linux-ibm (Ubuntu package) - addressed in versions 7.0.0-1008.8, 7.0.0-1010.10
linux-oem-7.0 (Ubuntu package) - update to 7.0.0-1009.9
linux-azure (Ubuntu package) - addressed in versions 7.0.0-1009.9, 7.0.0-1010.10
linux-aws (Ubuntu package) - addressed in versions 7.0.0-1009.9, 7.0.0-1015.15

• https://git.kernel.org/stable/c/8143a224785ceaf2b0856e08d4498916f38228fb
• https://git.kernel.org/stable/c/b74ad20198652b6b39a761c277ba65ae82b1e107
• https://git.kernel.org/stable/c/b7b9a461569734d33d3259d58d2507adfac107ed

• Improper resource shutdown or release in Linux kernel mptcp
• Debian update for linux
• Ubuntu update for linux-oem-7.0
• Ubuntu update for linux
• Ubuntu update for linux-ibm
• Ubuntu update for linux-azure
• Ubuntu update for linux-aws