Improper locking in Linux kernel - CVE-2026-31591
Published: April 25, 2026
Vulnerability identifier: #VU127805
CSH Severity: Low
CVSS v4: 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]
CVE-ID: CVE-2026-31591
CWE-ID: CWE-667
Exploitation vector: Local access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a local user to cause a denial of service.
The vulnerability exists due to improper locking in KVM SEV VMSA synchronization for SNP launch finish when synchronizing and encrypting VMSAs for SNP guests. A local user can manipulate or run a vCPU during synchronization to cause a denial of service.
The issue can corrupt vCPU state and may crash the host kernel.
Affected software
Linux kernel
Ubuntu
linux (Ubuntu package)
linux-azure (Ubuntu package)
linux-nvidia (Ubuntu package)
linux-raspi (Ubuntu package)
Ubuntu
linux (Ubuntu package)
linux-azure (Ubuntu package)
linux-nvidia (Ubuntu package)
linux-raspi (Ubuntu package)
How to mitigate CVE-2026-31591
Install security update from vendor's repository.
linux (Ubuntu package) - update to 7.0.0-27.27
linux-azure (Ubuntu package) - addressed in versions 7.0.0-1009.9, 7.0.0-1010.10
linux-nvidia (Ubuntu package) - update to 7.0.0-1013.13
linux-raspi (Ubuntu package) - update to 7.0.0-1014.14
linux-azure (Ubuntu package) - addressed in versions 7.0.0-1009.9, 7.0.0-1010.10
linux-nvidia (Ubuntu package) - update to 7.0.0-1013.13
linux-raspi (Ubuntu package) - update to 7.0.0-1014.14