CVE-2026-81627

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When using libvirt, set the following in the guest's domain XML:\n```\n<features>\n <apic/>\n <hyperv>\n <vapic state='off'/>\n </hyperv>\n</features>\n```\nWhen using QEMU directly, pass `-global kvmvapic.rom=off` on the command line.\n\nThis optimization is only used by 32-bit Windows guests for MMIO-based TPR register access. Linux guests, 64-bit Windows guests, and any guest using x2APIC or MSR-based TPR access are unaffected by disabling it."}], "timeline": [{"lang": "en", "time": "2026-09-18T00:00:00.000Z", "value": "Reported to Red Hat."}, {"lang": "en", "time": "2026-08-26T00:00:00.000Z", "value": "Made public."}], "credits": [{"lang": "en", "value": "Red Hat would like to thank Artem Dinaburg (Trail of Bits) for reporting this issue."}], "providerMetadata": {"orgId": "53f830b8-0a3f-465b-8143-3b8a9948e749", "shortName": "redhat", "dateUpdated": "2026-11-04T23:43:17.993Z"}, "x_generator": {"engine": "cvelib 1.8.0"}}, "adp": [{"references": [{"url": "https://gitlab.com/qemu-project/qemu/-/work_items/4206", "tags": ["exploit"]}], "metrics": [{"other": {"type": "ssvc", "content": {"timestamp": "2026-09-18T15:07:17.054544Z", "id": "CVE-2026-81627", "options": [{"Exploitation": "poc"}, {"Automatable": "no"}, {"Technical Impact": "total"}], "role": "CISA Coordinator", "version": "2.0.3"}}}], "title": "CISA ADP Vulnrichment", "providerMetadata": {"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2026-09-18T15:07:23.968Z"}}]}}

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