SB20260427196 - Double free in Linux kernel kasan
Published: April 27, 2026
Security Bulletin ID
SB20260427196
CSH Severity
Low
Patch available
YES
Number of vulnerabilities
1
Exploitation vector
Local access
Highest impact
Denial of service
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 1 vulnerability.
1) Double free (CVE-ID: CVE-2026-31686)
CWE-ID: CWE-415 - Double 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 double free in kasan_free_pxd() when freeing kasan page table entries during memory unmapping. A local user can trigger the vulnerable code path to cause a denial of service.
The issue was observed on powerpc systems with 64K page size where PUD tables can be allocated from the pgtable-2^9 slab cache.
Remediation
Install update from vendor's website.
References
- https://git.kernel.org/stable/c/51d8c78be0c27ddb91bc2c0263941d8b30a47d3b
- https://git.kernel.org/stable/c/85d98614e089a67dc6faa8ca766fe10a639f82b4
- https://git.kernel.org/stable/c/a05f77cb227c39c5069aea6f12762a29d1e6c103
- https://git.kernel.org/stable/c/b38237a2ea9c6c19836eee2c57037e1f9f103576
- https://git.kernel.org/stable/c/cec74b2ab7dff866b1d77eaa545b9e8fd14a1f87
- https://git.kernel.org/stable/c/f6204f7ff6aff62ce6242a76982c5ba3a9ded707