Microsoft Security Response Center guidance
Vendor revision: Aug 7, 2026CBL-Mariner Releases
Vendor-listed releases
- 6.6.145.2-1
Vulnerability intelligence
CVE-2026-64286 and is rated High severity with a CVSS score of 8.2. It is not in the current CISA KEV record we collected. That does not prove exploitation has not occurred.
CBL-Mariner Releases
Vendor-listed releases
In the Linux kernel, the following vulnerability has been resolved:
KVM: arm64: Clear __hyp_running_vcpu when flushing the pKVM hyp vCPU
flush_hyp_vcpu() copies the host vCPU context into the hyp's private vCPU on every run. ctxt_to_vcpu() expects a guest context to have a NULL __hyp_running_vcpu, which is only ever set on the host context, so that it resolves the vCPU via container_of().
While this is generally the case, flush_hyp_vcpu() copies the context verbatim and does not enforce this, so a value provided by the host is dereferenced at EL2 (host -> EL2).
Fix by clearing __hyp_running_vcpu after the copy.
Source: NVD