SB20261029133 - Use-after-free in Linux kernel sched

Description

This security bulletin contains information about 1 vulnerability.

1) Use-after-free (CVE-ID: CVE-2026-99167)

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 kernel memory corruption.

The vulnerability exists due to a use-after-free in __tcf_action_put() in the Linux kernel traffic control subsystem when concurrent operations release an action. A local user can trigger concurrent action releases to potentially cause a kernel crash: another thread may free the action after its reference count is decremented but before its binding count is updated, causing a write to freed memory.

Remediation

Install update from vendor's website.

References

• https://git.kernel.org/stable/c/2465d27ef90de9105c2bffb6c35f8ce08918e642
• https://git.kernel.org/stable/c/2e012e431aa271ef3c84206f48854f539c03bff0
• https://git.kernel.org/stable/c/7b16eb911091aae237a8673da94e4dfb9cd21d54