SB20260925139 - Use-after-free in Linux kernel arm64 mm
Published: September 25, 2026
Security Bulletin ID
SB20260925139
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) Use-after-free (CVE-ID: CVE-2026-93239)
CWE-ID: CWE-416 - Use After Free
CVSSv4: 5.7 [CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]
The vulnerability allows a local user to cause a kernel fault.
The vulnerability exists due to use-after-free in the arm64 show_pte() page-table walk when walking task page tables concurrently with teardown. A local user can cause a task page-table teardown to occur during the walk to cause a kernel fault.
The walk can also derive a lower-level pointer from a parent entry that has been cleared concurrently.
Remediation
Install update from vendor's website.
References
- https://git.kernel.org/stable/c/08d931a0a850ad16a64f2cd23a19f40795cdbdf7
- https://git.kernel.org/stable/c/0f05d95b99164a9ccc4cf4a4920e0ff0228138ad
- https://git.kernel.org/stable/c/68cbd70795dd8c06e7ccdc4eb0b74c5b180076c3
- https://git.kernel.org/stable/c/a77644d009dece1104b6fcc6e322b0e4503db0d6
- https://git.kernel.org/stable/c/b28fe65a36b8209b6adcf2722c7ce974cf9ac8d1