SB20260625200 - Use-after-free in Linux kernel cgroup

Description

This security bulletin contains information about 1 vulnerability.

1) Use-after-free (CVE-ID: CVE-2026-52991)

CWE-ID: CWE-416 - Use After Free

CVSSv4: CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear

The vulnerability allows a local user to cause a denial of service.

The vulnerability exists due to a use-after-free in pressure_write() in kernel/cgroup/cgroup.c when handling a write to a pressure cgroup file during concurrent cgroup file release. A local user can write crafted pressure data while racing cgroup file release to cause a denial of service.

The issue occurs because the of->priv pointer may be freed concurrently and later dereferenced.

Remediation

Install update from vendor's website.

References

• https://git.kernel.org/stable/c/03dc070fa0fc3cb4068693f468ccd5f8a7e58282
• https://git.kernel.org/stable/c/a5b98009f16d8a5fb4a8ff9a193f5735515c38fa
• https://git.kernel.org/stable/c/d4352c0709bfd38c752fccbde7fd72a82ac78f23