CVE-2020-6831: Canonical Ubuntu Linux

Critical severity, CVSS 9.8. EPSS: 5.8% chance of exploitation in the next 30 days.

A buffer overflow could occur when parsing and validating SCTP chunks in WebRTC. This could have led to memory corruption and a potentially exploitable crash. This vulnerability affects Firefox ESR < 68.8, Firefox < 76, and Thunderbird < 68.8.0.

Affected products

• Canonical Ubuntu Linux: version 16.04 only; version 18.04 only; version 19.10 only; version 20.04 only
• Debian Debian Linux: version 9.0 only; version 10.0 only
• Mozilla Firefox: before 76.0 (fixed in 76.0)
• Mozilla Firefox ESR: before 68.8.0 (fixed in 68.8.0)
• Mozilla Thunderbird: before 68.8.0 (fixed in 68.8.0)
• Opensuse Leap: version 15.2 only

Published 2020-05-26. Last modified 2026-06-17.