SB20260425124 - Improper locking in Linux kernel kvm svm
Published: April 25, 2026
Security Bulletin ID
SB20260425124
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-2026-31592)
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 sev_mem_enc_register_region() when handling KVM ioctls during SEV guest initialization failure paths. A local user can issue crafted ioctl calls to trigger a general protection fault and kernel crash.
The issue can occur if KVM_SEV_INIT{2} fails and KVM attempts to add to an uninitialized sev->regions_list.
Remediation
Install update from vendor's website.