Drupal 8.3.4 and Drupal 7.56 are maintenance releases which contain fixes for security vulnerabilities.

Updating your existing Drupal 8 and 7 sites is strongly recommended (see instructions for Drupal 8 and for Drupal 7). This release fixes security issues only; there are no new features nor non-security-related bug fixes in this release. See the 8.3.4 release notes and the 7.56 release notes for details on important changes and known issues affecting this release. Read on for details of the security vulnerabilities that were fixed in this release.

  • Advisory ID: DRUPAL-SA-CORE-2017-003
  • Project: Drupal core
  • Version: 7.x, 8.x
  • Date: 2017-June-21
  • Multiple vulnerabilities

Description

PECL YAML parser unsafe object handling - Critical - Drupal 8 - CVE-2017-6920

PECL YAML parser does not handle PHP objects safely during certain operations within Drupal core. This could lead to remote code execution.

File REST resource does not properly validate - Less Critical - Drupal 8 - CVE-2017-6921

The file REST resource does not properly validate some fields when manipulating files. A site is only affected by this if the site has the RESTful Web Services (rest) module enabled, the file REST resource is enabled and allows PATCH requests, and an attacker can get or register a user account on the site with permissions to upload files and to modify the file resource.

Files uploaded by anonymous users into a private file system can be accessed by other anonymous users - Moderately Critical - Drupal 7 and Drupal 8 - CVE-2017-6922

Private files that have been uploaded by an anonymous user but not permanently attached to content on the site should only be visible to the anonymous user that uploaded them, rather than all anonymous users. Drupal core did not previously provide this protection, allowing an access bypass vulnerability to occur. This issue is mitigated by the fact that in order to be affected, the site must allow anonymous users to upload files into a private file system.

The security team has also received reports that this vulnerability is being exploited for spam purposes, similar to the scenario discussed in PSA-2016-003 for the public file system.

Versions affected

  • Drupal core 7.x versions prior to 7.56
  • Drupal core 8.x versions prior to 8.3.4

Solution

Install the latest version:

Also see the Drupal core project page.

Reported by

PECL YAML parser unsafe object handling

File REST resource does not properly validate

Files uploaded by anonymous users into a private file system can be accessed by other anonymous users

Fixed by

PECL YAML parser unsafe object handling

File REST resource does not properly validate

Files uploaded by anonymous users into a private file system can be accessed by other anonymous users

Contact and More Information

The Drupal security team can be reached at security at drupal.org or via the contact form at https://www.drupal.org/contact.

Learn more about the Drupal Security team and their policies, writing secure code for Drupal, and securing your site.

Follow the Drupal Security Team on Twitter at https://twitter.com/drupalsecurity

Drupal version: