CVE-2019-17022: 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 does not escape &lt; and &gt; characters. Because the resulting string is pasted directly into the text node of the element this does not result in a direct injection into the webpage; however, if a webpage subsequently copies the node's innerHTML, assigning it to another innerHTML, this would result in an XSS vulnerability. Two WYSIWYG editors were identified with this behavior, more may exist. 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.