SB20260720100 - Improper locking in Linux kernel mm
Published: July 20, 2026
Security Bulletin ID
SB20260720100
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) Improper locking (CVE-ID: CVE-2026-64129)
CWE-ID: CWE-667 - Improper Locking
CVSSv4: 6.8 [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]
The vulnerability allows a local user to cause a denial of service.
The vulnerability exists due to improper locking in migrate_vma_insert_huge_pmd_page() in mm/migrate_device.c when handling an error from check_stable_address_space() after acquiring the PMD spinlock. A local user can trigger the affected code path to cause a denial of service.
The issue can leave the PMD spinlock permanently held, resulting in a deadlock.
Remediation
Install update from vendor's website.