SB2026082495 - Use-after-free in Linux kernel mm
Published: August 24, 2026
Breakdown by Severity
- 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.
References
- https://git.kernel.org/stable/c/26444eb71465c9934d9d418ef69c43f61185329b
- https://git.kernel.org/stable/c/39c6772b56a6bbdd62794833f74232971d94d7c9
- https://git.kernel.org/stable/c/3cc26c8907db0f5d1ff8043b5851ee572e9b3c98
- https://git.kernel.org/stable/c/7ac8a333dd41ba5e1b4e8c6edbc48b15446c5468
- https://git.kernel.org/stable/c/8d7f560f4b0482d469de962fbe4b59c37561052e
- https://git.kernel.org/stable/c/c5bf8cd148cfea948cfa3db71da427294b20db0f