Vulnerability Description
In the Linux kernel, the following vulnerability has been resolved: crypto: ccp - Do not initialize SNP for ioctl(SNP_VLEK_LOAD) Sashiko notes: > if SEV initialization fails and KVM is actively running normal VMs, could a > userspace process trigger this code path via /dev/sev ioctls (e.g., > SEV_PDH_GEN) and zero out MSR_VM_HSAVE_PA globally? Would the next VMRUN > execution for an active VM trigger a general protection fault and crash the > host? The SEV firmware docs for SNP_VLEK_LOAD note: > On SNP_SHUTDOWN, the VLEK is deleted. That is, the initialization/shutdown wrapper here is pointless, because the firmware immediately throws away the key anyway. Instead, refuse to do anything if SNP has not been previously initialized. This is an ABI break: before, this was a no-op and almost certainly a mistake by userspace, and now it returns -ENODEV. ABI compatibility could be maintained here by simply returning 0 in the check instead.
References
- https://git.kernel.org/stable/c/61cf5eef20657bff9ca235fe938a99ce5ff65c06
- https://git.kernel.org/stable/c/8836801847b9479ac046cb18a24981e1b0b05e9d
- https://git.kernel.org/stable/c/92567ed9306d5a3d1b007eb4faeff30cc3ffc3e4
- https://git.kernel.org/stable/c/f91e9dbb5845d1e5abf1028e6df57dcf61583e1b
FAQ
What is CVE-2026-64308?
CVE-2026-64308 is a documented vulnerability. In the Linux kernel, the following vulnerability has been resolved: crypto: ccp - Do not initialize SNP for ioctl(SNP_VLEK_LOAD) Sashiko notes: > if SEV initialization fails and KVM is actively run...
How severe is CVE-2026-64308?
CVSS scoring is not yet available for CVE-2026-64308. Check NVD for updates.
Is there a patch for CVE-2026-64308?
Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.