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{"affected": [{"affectedData": [{"defaultStatus": "unaffected", "product": "libxml2", "vendor": "xmlsoft", "versions": [{"lessThan": "2.15.4", "status": "affected", "version": "0", "versionType": "semver"}]}], "source": "cve@mitre.org"}], "cveTags": [], "descriptions": [{"lang": "en", "value": "In xmlIO in libxml2 before 2.15.4, an inconsistency in xmlOutputWriteCallback and xmlBufUse causes negative lengths to reach write callbacks, aka a lack of a check for integer overflow before calling writecallback. This has security relevance for many types of uses of that length value within a callback."}], "id": "CVE-2026-86143", "lastModified": "2026-09-05T05:17:13.270", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "HIGH", "attackVector": "LOCAL", "availabilityImpact": "LOW", "baseScore": 6.9, "baseSeverity": "MEDIUM", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:L", "version": "3.1"}, "exploitabilityScore": 1.4, "impactScore": 5.5, "source": "cve@mitre.org", "type": "Secondary"}]}, "published": "2026-09-05T05:17:13.270", "references": [{"source": "cve@mitre.org", "url": "https://github.com/GNOME/libxml2/commit/90f293ba74d28b1d570920382e707586f68ebf35"}, {"source": "cve@mitre.org", "url": "https://github.com/GNOME/libxml2/compare/v2.15.3...v2.15.4"}, {"source": "cve@mitre.org", "url": "https://gitlab.gnome.org/GNOME/libxml2/-/work_items/1111"}], "sourceIdentifier": "cve@mitre.org", "vulnStatus": "Received", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-192"}], "source": "cve@mitre.org", "type": "Primary"}]}

{}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "generic", "value": "[0,2.15.4)"}}], "enrichment": {"confidence": 95.0, "confidence_source": "inferred", "scores": [{"score": 95.0, "source": "inferred"}, {"score": 100.0, "source": "matching"}]}, "original": {"product": "libxml2", "source": "cna", "vendor": "xmlsoft"}, "product": "libxml2", "vendor": "xmlsoft"}], "created": "2026-09-05T05:30:17.527268+00:00", "title": "Integer Overflow in libxml2 Output Callbacks", "updated": "2026-09-05T06:30:04.893946+00:00", "vendors": ["xmlsoft", "xmlsoft$PRODUCT$libxml2"]}