{"id":"CVE-2026-90783","title":"MKVToolNix through 101.0 contains a heap buffer overflow in the bundled avilib library's ODML superindex parser due to integer wraparound in 32-bit arithmetic","summary":"MKVToolNix through 101.0 contains a heap buffer overflow in the bundled avilib library's ODML superindex parser due to integer wraparound in 32-bit arithmetic. Attackers can craft a malicious AVI file with oversized entry counts that cau…","severity":"high","cvss":7.8,"cvssVector":"CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H","cwe":["CWE-680"],"vendor":"Moritz Bunkus","product":"MKVToolNix","affected":["MKVToolNix <= 101.0"],"published":"2026-09-13","updated":"2026-09-24","sourceUpdated":"2026-09-24T20:43:32.537","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-90783","references":[{"url":"https://codeberg.org/mbunkus/mkvtoolnix","label":"disclosure@vulncheck.com"},{"url":"https://codeberg.org/mbunkus/mkvtoolnix/commit/1495126138e086080f0163bee27fafbdf956a1d0","label":"disclosure@vulncheck.com"},{"url":"https://codeberg.org/mbunkus/mkvtoolnix/src/tag/release-101.0/lib/avilib-0.6.10/avilib.c#L2552-L2570","label":"disclosure@vulncheck.com"},{"url":"https://www.vulncheck.com/advisories/mkvtoolnix-through-101.0-heap-buffer-overflow-via-avilib-odml-superindex-integer-wraparound","label":"disclosure@vulncheck.com"},{"url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-90783.json"},{"url":"https://access.redhat.com/security/cve/CVE-2026-90783"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-90783"}],"tags":["nvd","cve.org","csaf","vex","red-hat"],"epss":0.00202,"epssPercentile":0.09016,"ssvc":{"exploitation":"none","automatable":"no","technicalImpact":"total","timestamp":"2026-09-14T17:32:46.690815Z"},"ingestedAt":"2026-09-14T15:23:07.470Z","slug":"CVE-2026-90783","body":"## Overview\n\nMKVToolNix through 101.0 contains a heap buffer overflow in the bundled avilib library's ODML superindex parser due to integer wraparound in 32-bit arithmetic. Attackers can craft a malicious AVI file with oversized entry counts that cause an undersized heap allocation, allowing a heap buffer overflow when the file is parsed with mkvmerge.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.\n\n## Vendor advisories\n\n- **Red Hat VEX** · updated 2026-09-14 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-90783.json)","depth":"twilight","depthScore":43,"depthScoreParts":{"impact":42.9,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}