CVE-2026-42493

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{"affected": [{"affectedData": [{"defaultStatus": "unknown", "product": "Xen", "vendor": "Xen", "versions": [{"status": "unknown", "version": "consult Xen advisory XSA-495"}]}], "source": "security@xen.org"}], "cveTags": [], "descriptions": [{"lang": "en", "value": "Addressing certain issues, in particular related to operations which may\ntake excessively long and therefore would need preemption, has turned out\noverly costly. Since alternatives (HVM/PVH: HAP, PV: shim) are commonly\navailable, the decision was to deprecate the functionality, while still\nretaining it for people to use at their own (security) risk. Memory-wise\nsmall enough guests may still be okay to run."}], "id": "CVE-2026-42493", "lastModified": "2026-07-28T17:16:39.063", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "HIGH", "baseScore": 7.5, "baseSeverity": "HIGH", "confidentialityImpact": "NONE", "integrityImpact": "NONE", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H", "version": "3.1"}, "exploitabilityScore": 3.9, "impactScore": 3.6, "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "type": "Secondary"}], "ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-42493", "options": [{"exploitation": "none"}, {"automatable": "yes"}, {"technicalImpact": "partial"}], "role": "CISA Coordinator", "timestamp": "2026-07-28T15:58:19.075241Z", "version": "2.0.3"}}]}, "published": "2026-07-28T13:18:32.247", "references": [{"source": "security@xen.org", "url": "https://xenbits.xenproject.org/xsa/advisory-495.html"}, {"source": "af854a3a-2127-422b-91ae-364da2661108", "url": "http://www.openwall.com/lists/oss-security/2026/07/28/12"}, {"source": "af854a3a-2127-422b-91ae-364da2661108", "url": "http://xenbits.xen.org/xsa/advisory-495.html"}], "sourceIdentifier": "security@xen.org", "vulnStatus": "Deferred", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-400"}], "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "type": "Secondary"}]}

{}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "generic", "value": "consult Xen advisory XSA-495"}}], "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": "2026-07-28T22:00:05.940766+00:00", "updated": "2026-08-04T13:00:11.593784+00:00", "vendors": ["xen", "xen$PRODUCT$xen"]}