CVE-2026-23557

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{"affected": [{"affectedData": [{"defaultStatus": "unknown", "product": "Xen", "vendor": "Xen", "versions": [{"status": "unknown", "version": "consult Xen advisory XSA-484"}]}], "source": "security@xen.org"}], "configurations": [{"nodes": [{"cpeMatch": [{"criteria": "cpe:2.3:o:xen:xen:*:*:*:*:*:*:*:*", "matchCriteriaId": "37DFEBDB-42A9-4A8C-A040-CC08782EF553", "versionStartIncluding": "4.2.0", "vulnerable": true}], "negate": false, "operator": "OR"}]}], "cveTags": [], "descriptions": [{"lang": "en", "value": "Any guest can cause xenstored to crash by issuing a XS_RESET_WATCHES\ncommand within a transaction due to an assert() triggering.\n\nIn case xenstored was built with NDEBUG #defined nothing bad will\nhappen, as assert() is doing nothing in this case. Note that the\ndefault is not to define NDEBUG for xenstored builds even in release\nbuilds of Xen."}, {"lang": "es", "value": "Cualquier invitado puede hacer que xenstored falle al emitir un comando XS_RESET_WATCHES dentro de una transacci\u00f3n debido a que se activa un assert().\n\nEn caso de que xenstored se haya compilado con NDEBUG #definido, no ocurrir\u00e1 nada malo, ya que assert() no hace nada en este caso. Tenga en cuenta que el valor predeterminado es no definir NDEBUG para las compilaciones de xenstored, incluso en las compilaciones de lanzamiento de Xen."}], "id": "CVE-2026-23557", "lastModified": "2026-10-14T20:10:00.190", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "LOCAL", "availabilityImpact": "HIGH", "baseScore": 6.5, "baseSeverity": "MEDIUM", "confidentialityImpact": "NONE", "integrityImpact": "NONE", "privilegesRequired": "LOW", "scope": "CHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:H", "version": "3.1"}, "exploitabilityScore": 2.0, "impactScore": 4.0, "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "type": "Secondary"}], "ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-23557", "options": [{"exploitation": "none"}, {"automatable": "no"}, {"technicalImpact": "partial"}], "role": "CISA Coordinator", "timestamp": "2026-05-19T14:42:12.994792Z", "version": "2.0.3"}}]}, "published": "2026-05-19T14:16:38.817", "references": [{"source": "security@xen.org", "tags": ["Patch", "Vendor Advisory"], "url": "https://xenbits.xenproject.org/xsa/advisory-484.html"}, {"source": "af854a3a-2127-422b-91ae-364da2661108", "tags": ["Mailing List", "Patch", "Third Party Advisory"], "url": "http://www.openwall.com/lists/oss-security/2026/04/28/11"}, {"source": "af854a3a-2127-422b-91ae-364da2661108", "tags": ["Patch", "Vendor Advisory"], "url": "http://xenbits.xen.org/xsa/advisory-484.html"}], "sourceIdentifier": "security@xen.org", "vulnStatus": "Analyzed", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-617"}], "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "type": "Secondary"}]}

{}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "generic", "value": "[0,*]"}}], "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": "2026-05-19T14:45:07.491239+00:00", "updated": "2026-05-19T18:30:11.297688+00:00", "vendors": ["xen", "xen$PRODUCT$xen"]}