CVE-2017-6930 : What You Need to Know

Drupal Core versions prior to 8.4.5 are vulnerable to an access bypass issue when using node access controls on multilingual sites.

Understanding CVE-2017-6930

This CVE highlights a vulnerability in Drupal Core that could lead to access bypass on specific site configurations.

What is CVE-2017-6930?

In Drupal versions 8.4.x before 8.4.5, a security flaw exists where untranslated nodes are designated as default fallbacks for access queries, potentially allowing access bypass on multilingual sites.

The Impact of CVE-2017-6930

The vulnerability poses a risk of unauthorized access to content on affected Drupal sites, particularly those utilizing specific modules and configurations.

Technical Details of CVE-2017-6930

This section delves into the technical aspects of the vulnerability.

Vulnerability Description

The issue arises from Drupal marking untranslated nodes as default fallbacks for access queries, creating a loophole for access bypass.

Affected Systems and Versions

Product: Drupal Core
Vendor: Drupal.org
Vulnerable Versions: 8.4.x versions before 8.4.5

Exploitation Mechanism

The vulnerability can be exploited on sites that use the Content Translation module and a node access module like Domain Access implementing hook_node_access_records().

Mitigation and Prevention

Protecting systems from CVE-2017-6930 requires immediate actions and long-term security practices.

Immediate Steps to Take

Update Drupal Core to version 8.4.5 or later to mitigate the vulnerability.
Review and adjust node access controls to prevent unauthorized access.

Long-Term Security Practices

Regularly update Drupal Core and modules to patch security vulnerabilities.
Conduct security audits to identify and address potential risks.

Patching and Updates

Apply security patches promptly to ensure the latest fixes are in place.