CVE-2017-12801: Matroska LIBEBML2

Medium severity, CVSS 6.5. EPSS: 2.4% chance of exploitation in the next 30 days.

The UpdateDataSize function in ebmlmaster.c in libebml2 through 2012-08-26 allows remote attackers to cause a denial of service (assert fault) via a crafted mkv file.

Affected products

• Matroska LIBEBML2: up to and including 2012-08-26
• Matroska Mkclean: version 0.8.9 only
• Matroska Mkvalidator: version 0.5.1 only

Published 2017-11-10. Last modified 2026-06-17.