{"id":"CVE-2026-86143","aliases":[],"url":"https://o3.security/vulnerability/CVE-2026-86143","summary":null,"details":"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.","published":"2026-09-05T04:31:21.187Z","modified":"2026-09-10T08:16:09.112200Z","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"},"epss":{"score":0.00119,"percentile":0.0198,"asOf":"2026-09-07"},"cisaKev":null,"exploitsKnown":0,"affectedPackages":[],"fix":{"url":"https://github.com/GNOME/libxml2/commit/90f293ba74d28b1d570920382e707586f68ebf35","label":"GNOME/libxml2@90f293b"},"references":[{"type":"WEB","url":"https://github.com/GNOME/libxml2/compare/v2.15.3...v2.15.4"},{"type":"WEB","url":"https://gitlab.gnome.org/GNOME/libxml2/-/work_items/1111"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/86xxx/CVE-2026-86143.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-86143"},{"type":"FIX","url":"https://github.com/GNOME/libxml2/commit/90f293ba74d28b1d570920382e707586f68ebf35"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-09-10T08:16:09.112200Z"}}