SB2026062577 - Use-after-free in Linux kernel bpf

Description

This security bulletin contains information about 1 vulnerability.

1) Use-after-free (CVE-ID: CVE-2026-53085)

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 the open-coded task_vma iterator in kernel/bpf/task_iter.c when iterating a task's virtual memory areas while the target task exits concurrently. A local user can trigger the iterator on a task whose mm_struct is freed concurrently to cause a denial of service.

The issue occurs because task->mm is read locklessly and no mm reference is acquired before mmap_read_trylock().

Remediation

Install update from vendor's website.

References

• https://git.kernel.org/stable/c/239cec25a22662dbd80f57d94b38178c8be95269
• https://git.kernel.org/stable/c/43683bb280330f3d36f0f2a3932a4867b9603e9c
• https://git.kernel.org/stable/c/d0862de7c866c5bd7c32531f66738c21197af888
• https://git.kernel.org/stable/c/d8e27d2d22b6e2df3a0125b8c08e9aace38c954c