SB2026082495 - Use-after-free in Linux kernel mm



SB2026082495 - Use-after-free in Linux kernel mm

Published: August 24, 2026

Security Bulletin ID SB2026082495
CSH Severity
Low
Patch available
YES
Number of vulnerabilities 1
Exploitation vector Local access
Highest impact Code execution

Breakdown by Severity

Low 100%
  • Low
  • Medium
  • High
  • Critical

Description

This security bulletin contains information about 1 vulnerability.


1) Use-after-free (CVE-ID: CVE-2026-74672)

CWE-ID: CWE-416 - Use After Free

CVSSv4: 7.3 [CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N]


The vulnerability allows a local user to cause a denial of service or execute arbitrary code.

The vulnerability exists due to a use-after-free in kernel page table walking and vmap huge page table promotion logic when page tables are freed concurrently with debugging page table walks. A local user can trigger concurrent page table operations to cause a denial of service or execute arbitrary code.

The issue occurs because ptdump walks kernel page table ranges it does not own while huge vmap promotion can free lower page tables during the walk.


Remediation

Install update from vendor's website.