Improper Initialization in Linux kernel - CVE-2026-64310
Published: July 27, 2026
Vulnerability identifier: #VU139664
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-2026-64310
CWE-ID: CWE-665
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 initialization in the SEV ioctl handling in drivers/crypto/ccp/sev-dev.c when processing /dev/sev ioctl commands that require only SEV firmware. A local user can issue a crafted SEV ioctl request to cause a host crash.
The issue can occur if SEV initialization fails while KVM is actively running normal virtual machines, leading to global clearing of MSR_VM_HSAVE_PA and a general protection fault on the next VMRUN.
Affected software
Linux kernel
How to mitigate CVE-2026-64310
Install security update from vendor's repository.
Linux kernel - update to 7.0 rc3