CVE-2019-17016: Canonical Ubuntu Linux

Medium severity, CVSS 6.1. EPSS: 2% chance of exploitation in the next 30 days.

When pasting a &lt;style&gt; tag from the clipboard into a rich text editor, the CSS sanitizer incorrectly rewrites a @namespace rule. This could allow for injection into certain types of websites resulting in data exfiltration. This vulnerability affects Firefox ESR < 68.4 and Firefox < 72.

Affected products

  • Canonical Ubuntu Linux: version 16.04 only; version 18.04 only; version 19.04 only; version 19.10 only
  • Debian Debian Linux: version 8.0 only; version 9.0 only; version 10.0 only
  • Mozilla Firefox: before 72.0 (fixed in 72.0)
  • Mozilla Firefox ESR: before 68.4 (fixed in 68.4)
  • 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 7.7 only
  • Red Hat Enterprise Linux Server Tus: version 7.7 only
  • Red Hat Enterprise Linux Workstation: version 6.0 only; version 7.0 only

Published 2020-01-08. Last modified 2026-06-17.