Improper Validation of Specified Quantity in Input in Linux kernel - CVE-2026-31593
Published: April 25, 2026
Vulnerability identifier: #VU127807
CSH Severity: Low
CVSS v4.0: 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
CVE-ID: CVE-2026-31593
CWE-ID: CWE-1284
Exploitation vector: Local access
Exploit availability:
No public exploit available
Vendor: Linux Foundation
Affected software:
Linux kernel
Linux kernel
Detailed vulnerability description
The vulnerability allows a local user to cause a denial of service.
The vulnerability exists due to improper state validation in the KVM SEV VMSA synchronization logic when synchronizing vCPU state to an already-launched and encrypted vCPU. A local user can issue a crafted ioctl sequence to cause a denial of service.
On hosts with SNP enabled, accessing guest-private memory triggers an RMP page fault that panics the host. In SEV-ES environments without SNP, the issue may clobber guest state instead of panicking the host.
How to mitigate CVE-2026-31593
Install security update from vendor's repository.