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 7.8 HIGH

7.8^/10

CVSS v3 : HIGH

Vector :

Exploitability : 1.8 / Impact : 5.9

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://codeberg.org/mbunkus/mkvtoolnix
https://codeberg.org/mbunkus/mkvtoolnix/commit/1495126138e086080f0163bee27fafbdf956a1d0
https://codeberg.org/mbunkus/mkvtoolnix/src/tag/release-101.0/lib/avilib-0.6.10/avilib.c#L2552-L2570
https://www.vulncheck.com/advisories/mkvtoolnix-through-101.0-heap-buffer-overflow-via-avilib-odml-superindex-integer-wraparound

Configurations

No configuration.

History

No history.

Information

Published : 2026-09-13 13:16

Updated : 2026-09-14 19:18

NVD link : CVE-2026-90783

Mitre link : CVE-2026-90783

CVE.ORG link : CVE-2026-90783

JSON object : View

Products Affected

No product.

CWE

CWE-680

Integer Overflow to Buffer Overflow

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