{"id":"CVE-2026-79611","url":"https://www.cyber-defence.io/tools/cve/CVE-2026-79611","generatedAt":"2026-10-28T01:51:37.467Z","title":"For XSA-308 logic was introduced, as VMX VMEntry checks do not like the exact combination of state which occurs when #DB in intercepted, Single Stepping is active, and blocked by STI/MovSS is active, despite this being a legitimate state to be in.","description":"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.","published":"2026-10-13T16:17:23.000Z","lastModified":"2026-10-20T18:17:22.000Z","status":"Awaiting Analysis","sourceIdentifier":"security@xen.org","cvss":{"version":"3.1","score":5.5,"severity":"MEDIUM","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H"},"cwe":["CWE-843"],"affected":[],"epss":{"score":0.00161,"percentile":0.05203,"date":"2026-10-26","history":[{"date":"2026-10-14","score":0.00169,"percentile":0.05874}]},"kev":{"listed":false},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"low","text":"Lower severity and a low EPSS score (0.16%). Track it; it rarely justifies an emergency change on its own."},"changes":[{"kind":"scored","label":"Newly scored","at":"2026-10-20T19:15:07.000Z","detail":{"from":null,"score":"5.5","severity":"MEDIUM","fromSeverity":null},"summary":"Now scored CVSS 5.5 MEDIUM."},{"kind":"new","label":"New CVE","at":"2026-10-13T16:17:23.000Z","detail":{"score":null,"severity":null,"publishedAt":"2026-10-13T16:17:23.347Z"},"summary":"New CVE, medium severity (CVSS 5.5)."}],"references":[{"url":"https://xenbits.xenproject.org/xsa/advisory-518.html","source":"security@xen.org"},{"url":"http://www.openwall.com/lists/oss-security/2026/10/13/7","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"http://xenbits.xen.org/xsa/advisory-518.html","source":"af854a3a-2127-422b-91ae-364da2661108"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-79611","epss":"https://www.first.org/epss/","kev":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","exploitdb":"https://www.exploit-db.com/"},"licence":"CC BY 4.0 — link back to the CVE Explorer if you publish the results; upstream data remains subject to its own terms."}