CVE-2026-64172

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 v3 7.1 HIGH

7.1^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.5 / Impact : 4.0

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope CHANGED

References

Link	Resource
https://git.kernel.org/stable/c/94ade38f317ea086a181db0e6b69c574b3b70a5e
https://git.kernel.org/stable/c/9560e6fee887a9594a89fa265b5b9c79b1591803
https://git.kernel.org/stable/c/9a12fa5213cfc391e0eed63902d3be98f0913765

Configurations

No configuration.

History

20 Jul 2026, 15:17

Type	Values Removed	Values Added
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 7.1

19 Jul 2026, 16:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-07-19 16:17

Updated : 2026-07-20 15:17

NVD link : CVE-2026-64172

Mitre link : CVE-2026-64172

CVE.ORG link : CVE-2026-64172

JSON object : View

Products Affected

No product.

CWE

No CWE.

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