{"api_version":"1","generated_at":"2026-09-05T09:13:03+00:00","cve":"CVE-2026-86143","urls":{"html":"https://cve.report/CVE-2026-86143","api":"https://cve.report/api/cve/CVE-2026-86143.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-86143","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-86143"},"summary":{"title":"CVE-2026-86143","description":"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.","state":"PUBLISHED","assigner":"mitre","published_at":"2026-09-05 05:17:13","updated_at":"2026-09-05 05:17:13"},"problem_types":["CWE-192","CWE-192 CWE-192 Integer Coercion Error"],"metrics":[{"version":"3.1","source":"cve@mitre.org","type":"Secondary","score":"6.9","severity":"MEDIUM","vector":"CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:L","data":{"version":"3.1","vectorString":"CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:L","baseScore":6.9,"baseSeverity":"MEDIUM","attackVector":"LOCAL","attackComplexity":"HIGH","privilegesRequired":"NONE","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"HIGH","integrityImpact":"HIGH","availabilityImpact":"LOW"}},{"version":"3.1","source":"CNA","type":"CVSS","score":"6.9","severity":"MEDIUM","vector":"CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:L","data":{"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"}}],"references":[{"url":"https://gitlab.gnome.org/GNOME/libxml2/-/work_items/1111","name":"https://gitlab.gnome.org/GNOME/libxml2/-/work_items/1111","refsource":"cve@mitre.org","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://github.com/GNOME/libxml2/commit/90f293ba74d28b1d570920382e707586f68ebf35","name":"https://github.com/GNOME/libxml2/commit/90f293ba74d28b1d570920382e707586f68ebf35","refsource":"cve@mitre.org","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://github.com/GNOME/libxml2/compare/v2.15.3...v2.15.4","name":"https://github.com/GNOME/libxml2/compare/v2.15.3...v2.15.4","refsource":"cve@mitre.org","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-86143","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-86143","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"xmlsoft","product":"libxml2","version":"affected 2.15.4 semver","platforms":[]}],"timeline":[],"solutions":[],"workarounds":[],"exploits":[],"credits":[],"nvd_cpes":[],"vendor_comments":[],"enrichments":{"kev":null,"epss":null,"legacy_qids":[]},"source_records":{"cve_program":{"containers":{"cna":{"affected":[{"defaultStatus":"unaffected","product":"libxml2","vendor":"xmlsoft","versions":[{"lessThan":"2.15.4","status":"affected","version":"0","versionType":"semver"}]}],"cpeApplicability":[{"nodes":[{"cpeMatch":[{"criteria":"cpe:2.3:a:xmlsoft:libxml2:*:*:*:*:*:*:*:*","versionEndExcluding":"2.15.4","vulnerable":true}],"negate":false,"operator":"OR"}]}],"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."}],"metrics":[{"cvssV3_1":{"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"},"format":"CVSS","scenarios":[{"lang":"en","value":"GENERAL"}]}],"problemTypes":[{"descriptions":[{"cweId":"CWE-192","description":"CWE-192 Integer Coercion Error","lang":"en","type":"CWE"}]}],"providerMetadata":{"dateUpdated":"2026-09-05T04:31:21.187Z","orgId":"8254265b-2729-46b6-b9e3-3dfca2d5bfca","shortName":"mitre"},"references":[{"url":"https://github.com/GNOME/libxml2/compare/v2.15.3...v2.15.4"},{"url":"https://github.com/GNOME/libxml2/commit/90f293ba74d28b1d570920382e707586f68ebf35"},{"url":"https://gitlab.gnome.org/GNOME/libxml2/-/work_items/1111"}],"x_generator":{"engine":"CVE-Request-form 0.0.1"}}},"cveMetadata":{"assignerOrgId":"8254265b-2729-46b6-b9e3-3dfca2d5bfca","assignerShortName":"mitre","cveId":"CVE-2026-86143","datePublished":"2026-09-05T04:31:21.187Z","dateReserved":"2026-09-05T04:31:20.849Z","dateUpdated":"2026-09-05T04:31:21.187Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-09-05 05:17:13","lastModifiedDate":"2026-09-05 05:17:13","problem_types":["CWE-192","CWE-192 CWE-192 Integer Coercion Error"],"metrics":{"cvssMetricV31":[{"source":"cve@mitre.org","type":"Secondary","cvssData":{"version":"3.1","vectorString":"CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:L","baseScore":6.9,"baseSeverity":"MEDIUM","attackVector":"LOCAL","attackComplexity":"HIGH","privilegesRequired":"NONE","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"HIGH","integrityImpact":"HIGH","availabilityImpact":"LOW"},"exploitabilityScore":1.4,"impactScore":5.5}]},"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"86143","Ordinal":"1","Title":"CVE-2026-86143","CVE":"CVE-2026-86143","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"86143","Ordinal":"1","NoteData":"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.","Type":"Description","Title":"CVE-2026-86143"}]}}}