SB2026102211 - Use-after-free in Linux kernel sched
Published: October 22, 2026
Breakdown by Severity
- 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.
References
- https://git.kernel.org/stable/c/2b783c562c3238ff50c34fd7a72a735c9cc73d9a
- https://git.kernel.org/stable/c/4a04ed91575819fb1859311113e95700b709bec7
- https://git.kernel.org/stable/c/b097d9d7a5b09c8ec5c4c1a08e35ac5a66b06b44
- https://git.kernel.org/stable/c/c812bb4aea13d385d048b5b24756aee2edf6f99e
- https://git.kernel.org/stable/c/f85009dfcd65e5969526b0db7a49b5413746e630