Microsoft Security Response Center guidance
Vendor revision: Nov 5, 2026Release Notes
Vulnerability intelligence
CVE-2026-46032 and is rated Medium severity with a CVSS score of 5.5. It is not in the current CISA KEV record we collected. That does not prove exploitation has not occurred.
Release Notes
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.
Source: NVD