SB20261022137 - Use-after-free in Linux kernel smc



SB20261022137 - Use-after-free in Linux kernel smc

Published: October 22, 2026

Security Bulletin ID SB20261022137
CSH Severity
Low
Patch available
YES
Number of vulnerabilities 1
Exploitation vector Local access
Highest impact Denial of service

Breakdown by Severity

Low 100%
  • Low
  • Medium
  • High
  • Critical

Description

This security bulletin contains information about 1 vulnerability.


1) Use-after-free (CVE-ID: CVE-2026-98559)

CWE-ID: CWE-416 - Use After Free

CVSSv4: 5.7 [CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]


The vulnerability allows a local user to potentially cause a denial of service through invalid kernel memory access.

The vulnerability exists due to use-after-free in the Linux kernel SMC function smcr_port_err() when traversing smc_lgr_list.list without holding smc_lgr_list.lock. A local user can potentially trigger a race between this traversal and concurrent smc_lgr_terminate_sched() execution to cause a denial of service by dereferencing a freed link group.


Remediation

Install update from vendor's website.