CVE Catalog

CVE-2026-64172

HighCVSS 7.1
Published: Updated: Translated: NVD NIST

Exploitation Probability (EPSS)

Low risk
0.14%

3th percentile - higher than 3% of all known CVEs

Summary

A vulnerability in the KVM driver for Hygon Family 18h CPUs causes hardware to read a stale IsRunning=1 bit during ICR write emulation, failing to generate an AVIC_IPI_FAILURE_TARGET_NOT_RUNNING VM-Exit. This leads to hung vCPUs and unbounded delays in guest execution.

Risk Assessment

The organization risks virtual machine hangs and unpredictable delays in guest application performance, potentially causing service disruptions and performance degradation.

Recommendation

Apply the Linux kernel patch that extends the AMD Family 17h erratum #1235 workaround to Hygon Family 18h processors, disabling AVIC IPI virtualization.

Other vulnerabilities in Linux kernel

See all
Original NVD description (English source)

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.

Vulnerability data from NVD (NIST) · CISA KEV · EPSS