Use-after-free in Linux kernel - CVE-2026-89636
Published: September 12, 2026
Vulnerability identifier: #VU149165
CSH Severity: Low
CVSS v4: 0 [CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:N/VI:N/VA:N/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-89636
CWE-ID: CWE-416
Exploitation vector: Local access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a local user to cause a use-after-free.
The vulnerability exists due to use-after-free in the SMB client DFS cache's free_tgts() function when using ce->tgthint after its target entries have been freed. A local user can trigger use of the stale target cache hint to cause a use-after-free.
Affected software
Linux kernel
How to mitigate CVE-2026-89636
Install security update from vendor's repository.