MKVToolNix through 101.0 Heap Buffer Overflow via avilib ODML Superindex Integer Wraparound
Priority LOW 38CWE-680Published · Updated
Key facts
- Attack vector
- Local
- Privileges required
- None
- User interaction
- Passive
- Attack complexity
- Low
- Attack requirements
- None
- Impact type
- —
- Confidentiality · integrity · availability
- High · High · High
- Fix status
- Fixed
Attack profile from CVSS 4.0 · CNA. Fix status from CNA.
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 cause an undersized heap allocation, allowing a heap buffer overflow when the file is parsed with mkvmerge.
Why it matters now
Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00202 10th percentileScored 2026-11-07
Fix Fixed No fixed version in the sources yet
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Total
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| Moritz Bunkus | MKVToolNix | up to 101.0 | — | Patch available | CNA |
- MKVToolNix VendorMoritz Bunkus Affected up to 101.0 Fixed in — Patch available CNA
Remediation
No fixed version listed by the sources yet.
Vendor assessments
Timeline
- 2026-10-02 Threatist record created from CVE-2026-90783
- 2026-10-03 Alias added: GHSA-x9xf-h66v-mjmc
References
Sources
- CVE-2026-90783 · CVE Program
- CVE-2026-90783 · NVD
- FIRST EPSS
- GHSA-x9xf-h66v-mjmc · GitHub Advisory Database · CC BY 4.0
- CVE-2026-90783 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences