PT-2026-64528 · Linux · Linux
CVE-2026-64307
·
Published
2026-07-25
·
Updated
2026-07-25
None
No severity ratings or metrics are available. When they are, we'll update the corresponding info on the page.
In the Linux kernel, the following vulnerability has been resolved:
crypto: ccp - Do not initialize SNP for ioctl(SNP CONFIG)
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?
Refuse to re-try initialization if SNP is not already initialized for
SNP CONFIG.
This is technically an ABI break: before if SNP initialization failed it
could be transparently retriggered by this ioctl, and if no VMs were
running, everything worked fine. Hopefully this is enough of a corner case
that nobody will notice, but someone does, there are a few options:
- do something like symbol get() for kvm and refuse to initialize if KVM is loaded
- check each cpu's HSAVE PA for non-zero data before re-initializing
- once initialization has failed, continue to refuse to initialize until the ccp module is unloaded
Found an issue in the description? Have something to add? Feel free to write us 👾
Related Identifiers
Affected Products
Linux