CVE-2026-79603

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{"affected": [{"affectedData": [{"defaultStatus": "unknown", "product": "Xen", "vendor": "Xen", "versions": [{"status": "unknown", "version": "consult Xen advisory XSA-511"}]}], "source": "security@xen.org"}], "cveTags": [], "descriptions": [{"lang": "en", "value": "x86 PV guests can free memory pages while still keeping a stale TLB entry\npointing to them. A TLB flush is only issued by Xen (if needed) when the\npage is re-used. Since it's possible for the page to be scrubbed ahead of\nthe TLB flush, there's a window where a PV guest can modify an already\nscrubbed page."}], "id": "CVE-2026-79603", "lastModified": "2026-09-08T19:20:25.117", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "NONE", "baseScore": 4.3, "baseSeverity": "MEDIUM", "confidentialityImpact": "LOW", "integrityImpact": "NONE", "privilegesRequired": "LOW", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N", "version": "3.1"}, "exploitabilityScore": 2.8, "impactScore": 1.4, "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "type": "Secondary"}], "ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-79603", "options": [{"exploitation": "none"}, {"automatable": "no"}, {"technicalImpact": "partial"}], "role": "CISA Coordinator", "timestamp": "2026-09-08T13:42:37.092287Z", "version": "2.0.3"}}]}, "published": "2026-09-08T13:17:27.253", "references": [{"source": "security@xen.org", "url": "https://xenbits.xenproject.org/xsa/advisory-511.html"}, {"source": "af854a3a-2127-422b-91ae-364da2661108", "url": "http://www.openwall.com/lists/oss-security/2026/09/08/8"}, {"source": "af854a3a-2127-422b-91ae-364da2661108", "url": "http://xenbits.xen.org/xsa/advisory-511.html"}], "sourceIdentifier": "security@xen.org", "vulnStatus": "Awaiting Analysis", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-664"}], "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "type": "Secondary"}]}

{}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "generic", "value": "consult Xen advisory XSA-511"}}], "enrichment": {"confidence": 100.0, "confidence_source": "matching", "scores": [{"score": 100.0, "source": "matching"}]}, "original": {"product": "Xen", "source": "cna", "vendor": "Xen"}, "product": "xen", "vendor": "xen"}], "created": "2026-09-08T14:00:19.346628+00:00", "updated": "2026-09-10T03:15:16.718186+00:00", "vendors": ["xen", "xen$PRODUCT$xen"]}