CVE-2026-64307

Summary

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

Impact & exploitability

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Affected products we track (1)

Recommendation

Apply the vendor fix in your normal patch cycle. Open any affected product above for its exact safe version.

Official patch: https://git.kernel.org/stable/c/08f0e65e784c4b20e6e620dd4f68d8636073a3d2 ↗

Additional information

• NVD record
• https://git.kernel.org/stable/c/08f0e65e784c4b20e6e620dd4f68d8636073a3d2Patch
• https://git.kernel.org/stable/c/20f548cdac94860a164e5ebba4f7e4a01051cb06Patch
• https://git.kernel.org/stable/c/345a6e869b33687e9268044bcaeeefd7c61da675Patch
• https://git.kernel.org/stable/c/441ea32cf2755a0dc593557056b00b7caa0651f5Patch