Vulnerability Description
In the Linux kernel, the following vulnerability has been resolved: KVM: SVM: Disable AVIC IPI virtualization on Hygon Family 18h (erratum #1235) Hygon Family 18h CPUs are derived from AMD Family 17h (Zen1) silicon and share the same erratum #1235: hardware may read a stale IsRunning=1 bit during ICR write emulation and silently fail to generate an AVIC_IPI_FAILURE_TARGET_NOT_RUNNING VM-Exit on the sending vCPU. The absence of the VM-Exit causes KVM to miss the required wakeup of blocking target vCPUs, leading to hung vCPUs and unbounded delays in guest execution. Extend the existing AMD Family 17h erratum #1235 workaround to also cover Hygon Family 18h. With IPI virtualization disabled, KVM never sets IsRunning=1 in the Physical ID table, so every non-self IPI generates a VM-Exit and is correctly emulated.
CVSS Score
HIGH
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Linux | Linux Kernel | >= 6.17, < 6.18.34 |
References
- https://git.kernel.org/stable/c/94ade38f317ea086a181db0e6b69c574b3b70a5ePatch
- https://git.kernel.org/stable/c/9560e6fee887a9594a89fa265b5b9c79b1591803Patch
- https://git.kernel.org/stable/c/9a12fa5213cfc391e0eed63902d3be98f0913765Patch
FAQ
What is CVE-2026-64172?
CVE-2026-64172 is a vulnerability with a CVSS score of 7.1 (HIGH). In the Linux kernel, the following vulnerability has been resolved: KVM: SVM: Disable AVIC IPI virtualization on Hygon Family 18h (erratum #1235) Hygon Family 18h CPUs are derived from AMD Family 17...
How severe is CVE-2026-64172?
CVE-2026-64172 has been rated HIGH with a CVSS base score of 7.1/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-64172?
Check the references section above for vendor advisories and patch information. Affected products include: Linux Linux Kernel.