SB2026102211 - Use-after-free in Linux kernel sched



SB2026102211 - Use-after-free in Linux kernel sched

Published: October 22, 2026

Security Bulletin ID SB2026102211
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-2026-98441)

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 cause kernel memory corruption and potentially a denial of service.

The vulnerability exists due to use-after-free in the Linux kernel act_ct connection tracking action when cloned packets share an unconfirmed connection tracking entry and are processed with different extension sets. A local user can trigger processing in which one clone installs a helper extension but remains unconfirmed, and another adds extensions for labels or NAT, invalidating a pointer in the expectation list, to cause access to freed memory during subsequent destruction.


Remediation

Install update from vendor's website.