CVE-2026-46032

/// Technical description

In the Linux kernel, the following vulnerability has been resolved:

KVM: nSVM: Triple fault if restore host CR3 fails on nested #VMEXIT

If loading L1's CR3 fails on a nested #VMEXIT, nested_svm_vmexit()

returns an error code that is ignored by most callers, and continues to

run L1 with corrupted state. A sane recovery is not possible in this

case, and HW behavior is to cause a shutdown. Inject a triple fault

instead, and do not return early from nested_svm_vmexit(). Continue

cleaning up the vCPU state (e.g. clear pending exceptions), to handle

the failure as gracefully as possible.

From the APM:

Upon #VMEXIT, the processor performs the following actions in order to

return to the host execution context:

...

if (illegal host state loaded, or exception while loading host state)

shutdown

else

execute first host instruction following the VMRUN

Remove the return value of nested_svm_vmexit(), which is mostly

unchecked anyway.

/// Remediation

Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

/// References