Vulnerability in Moritz Bunkus Mkvtoolnix
CVE-2026-90783
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 cause an undersized heap allocation, allowing a heap buffer overflow when the file is parsed with mkvmerge.
CVSS v3 metric
CVSS v3 base score 7.8 (High). Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H.
Affected products
Weakness classification (CWE)
References
- disclosure@vulncheck.com (patch)
- disclosure@vulncheck.com (technical-description)
- disclosure@vulncheck.com (product)
- disclosure@vulncheck.com (third-party-advisory)
Frequently asked questions
- What is CVE-2026-90783?
- CVE-2026-90783 is a high-severity vulnerability in Moritz Bunkus Mkvtoolnix, classified under Integer Overflow to Buffer Overflow. CVSS score: 7.8/10. Published 2026-09-13.
- How severe is CVE-2026-90783?
- High severity. CVSS v3 base score is 7.8 out of 10.