CVE-2026-90783 [HIGH] – MKVToolNix through 101.0 contains a heap buffer overflow in the bundled avilib library’s O

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.