{"cve":"CVE-2026-64172","nvd":{"published":"2026-07-19T16:17:59.383","modified":"2026-08-13T15:32:19.817","status":"Analyzed","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nKVM: SVM: Disable AVIC IPI virtualization on Hygon Family 18h (erratum #1235)\n\nHygon Family 18h CPUs are derived from AMD Family 17h (Zen1) silicon and\nshare the same erratum #1235: hardware may read a stale IsRunning=1 bit\nduring ICR write emulation and silently fail to generate an\nAVIC_IPI_FAILURE_TARGET_NOT_RUNNING VM-Exit on the sending vCPU.\n\nThe absence of the VM-Exit causes KVM to miss the required wakeup of\nblocking target vCPUs, leading to hung vCPUs and unbounded delays in\nguest execution.\n\nExtend the existing AMD Family 17h erratum #1235 workaround to also cover\nHygon Family 18h.  With IPI virtualization disabled, KVM never sets\nIsRunning=1 in the Physical ID table, so every non-self IPI generates a\nVM-Exit and is correctly emulated.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H","score":7.1},"cwes":[],"references":["https://git.kernel.org/stable/c/94ade38f317ea086a181db0e6b69c574b3b70a5e","https://git.kernel.org/stable/c/9560e6fee887a9594a89fa265b5b9c79b1591803","https://git.kernel.org/stable/c/9a12fa5213cfc391e0eed63902d3be98f0913765"],"products":["linux:linux_kernel"],"source":"nvd","synced_at":"2026-10-19T22:45:36.895656543+00:00"},"epss":{"cve":"CVE-2026-64172","score":0.00195,"percentile":0.09232,"date":"2026-10-31"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}