CVE-2018-5156: Canonical Ubuntu Linux

Critical severity, CVSS 9.8. EPSS: 3.8% chance of exploitation in the next 30 days.

A vulnerability can occur when capturing a media stream when the media source type is changed as the capture is occurring. This can result in stream data being cast to the wrong type causing a potentially exploitable crash. This vulnerability affects Thunderbird < 60, Firefox ESR < 60.1, Firefox ESR < 52.9, and Firefox < 61.

Affected products

• Canonical Ubuntu Linux: version 14.04 only; version 16.04 only; version 17.10 only; version 18.04 only
• Debian Debian Linux: version 8.0 only; version 9.0 only
• Mozilla Firefox: before 52.9.0 (fixed in 52.9.0); before 61.0 (fixed in 61.0); from 52.9.1, before 60.1.0 (fixed in 60.1.0)
• Mozilla Thunderbird: before 60.0 (fixed in 60.0)
• Red Hat Enterprise Linux Desktop: version 6.0 only; version 7.0 only
• Red Hat Enterprise Linux Server: version 6.0 only; version 7.0 only
• Red Hat Enterprise Linux Server Aus: version 7.6 only
• Red Hat Enterprise Linux Server Eus: version 7.5 only; version 7.6 only
• Red Hat Enterprise Linux Server Tus: version 7.6 only
• Red Hat Enterprise Linux Workstation: version 6.0 only; version 7.0 only

Published 2018-10-18. Last modified 2026-06-17.