CVEvulnerability
CVE-2026-64172
7.1 HIGH
Official page ↗
- Status
- Analyzed
- Published
- 2026-07-19
- Last modified
- 2026-08-13
- Assigner
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67
- CVSS 3.1 (416baaa9-dc9f-4396-8d5f-8c081fb06d67)
- 7.1 HIGH — CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
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.
Affected configurations
• linux linux kernel (>= 6.17 < 6.18.34)
• linux linux kernel (>= 6.19 < 7.0.11)
• linux linux kernel 7.1