SB2026040318 - Use-after-free in Linux kernel mm

Description

This security bulletin contains information about 1 vulnerability.

1) Use-after-free (CVE-ID: CVE-2026-23415)

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 use-after-free in __futex_key_to_node() when processing futex operations during a race with vma policy replacement. A local user can trigger concurrent futex activity and memory policy changes to cause a denial of service.

The issue is caused by a race between futex_key_to_node_opt() and vma_replace_policy() that leads to a use-after-free read of mpol->mode from a freed mempolicy pointer.

Remediation

Install update from vendor's website.

References

• https://git.kernel.org/stable/c/190a8c48ff623c3d67cb295b4536a660db2012aa
• https://git.kernel.org/stable/c/7e196194ea27bd49adf3551e2aceb83498eb73fe
• https://git.kernel.org/stable/c/853f70c67d1b37e368fdcb3e328c4b8c04f53ac0