CVE-2017-6927

Drupal 8.4.x versions before 8.4.5 and Drupal 7.x versions before 7.57 has
a Drupal.checkPlain() JavaScript function which is used to escape
potentially dangerous text before outputting it to HTML (as JavaScript
output does not typically go through Twig autoescaping). This function does
not correctly handle all methods of injecting malicious HTML, leading to a
cross-site scripting vulnerability under certain circumstances. The PHP
functions which Drupal provides for HTML escaping are not affected.

Bugs

• <http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=891150&gt;