CVE-2017-6927

Description

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.

How to fix CVE-2017-6927

To remediate CVE-2017-6927, upgrade the affected package to a fixed version below.

• —upgrade to 7.14-2+deb7u17 or later
• —upgrade to 7.32-1+deb8u10 or later
• —upgrade to 8.4.5 or later
• —upgrade to 8.4.5 or later

Is CVE-2017-6927 being exploited?

Low — EPSS is 1.4%, meaning exploitation activity has not been observed at scale.

Affected packages (4)

• from 0, < 7.14-2+deb7u17
• from 0, < 7.32-1+deb8u10
• >= 8.4.0, < 8.4.5
• >= 8.4.0, < 8.4.5

CVSS scores

References (8)

• ADVISORYnvd.nist.gov/vuln/detail/CVE-2017-6927
• PATCHgithub.com/drupal/core
• WEBgithub.com/FriendsOfPHP/security-advisories/blob/master/drupal/core/CVE-2017-6927.yaml
• WEBgithub.com/FriendsOfPHP/security-advisories/blob/master/drupal/drupal/CVE-2017-6927.yaml