{"schema":"threatline.record/2","record":{"id":"CVE-2026-79611","aliases":[],"summary":"VMX: VMentry failure with branch tracing and blocked states","details":"For XSA-308 logic was introduced, as VMX VMEntry checks do not like the\nexact combination of state which occurs when #DB in intercepted, Single\nStepping is active, and blocked by STI/MovSS is active, despite this being\na legitimate state to be in.  The resulting VMEntry failure is fatal to\nthe guest.\n\nSadly there is another special sub-case of the above, with branch tracing\nenabled.  In that case the prior adjustment would still cause a VMentry\nfailure, as before fatal to the guest.","categories":["Unclassified"],"product":"Xen","vendor":"Xen","ecosystem":null,"affected_ranges":[{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-79611","source_modified_at":"2026-10-20T17:31:41.971Z","fetched_at":"2026-10-23T18:45:31.882637Z","product":"Xen","vendor":"Xen","versions":[{"status":"unknown","version":"consult Xen advisory XSA-518"}],"defaultStatus":"unknown"}],"fixed_versions":[],"cvss":5.5,"severity":"Medium","kev":{"listed":false},"epss":{"probability":0.00123,"percentile":0.01912,"score_date":"2026-10-23"},"published_at":"2026-10-13T15:44:56.361Z","modified_at":"2026-10-20T17:31:41.971Z","provenance":[{"source":"CVE List","url":"https://www.cve.org/CVERecord?id=CVE-2026-79611","fetched_at":"2026-10-23T18:45:31.882637Z","source_modified_at":"2026-10-20T17:31:41.971Z"},{"source":"EPSS","url":"https://api.first.org/data/v1/epss?cve=CVE-2026-79611","fetched_at":"2026-10-23T18:42:43.628194Z","source_modified_at":"2026-10-23"}],"sources":["CVE List","EPSS"],"references":[{"source":"CVE List","url":"https://xenbits.xenproject.org/xsa/advisory-518.html"}],"locations":[],"motoko_assessment":{"status":"requires_architecture_review","automatic_remediation":false},"cve_state":"PUBLISHED","cvss_source":"CISA ADP","ssvc":{"exploitation":"none","automatable":"no","technical_impact":"partial","assessed_at":"2026-10-20T17:31:36.841344Z"},"classification":{"method":"product-first software-layer rules","rules_version":"2.1","matched_on":null,"confidence":"unknown","reviewed":false},"change_timestamp":"2026-10-20T17:31:41.971Z","content_hash":"b5c3789cbc4b044ad67338477dc8004e286288d8fa944495bc24bda75e0dc636"}}