Source: cve@mitre.org
The CCK Comment Reference module 5.x before 5.x-1.2 and 6.x before 6.x-1.3, a module for Drupal, allows remote attackers to bypass intended access restrictions and read comments by using the autocomplete path.
Drupal websites using vulnerable versions of the CCK Comment Reference module are susceptible to a critical vulnerability allowing attackers to bypass access controls and read sensitive comments. This can lead to information disclosure and potentially further compromise of the affected system. Successful exploitation requires no authentication and can be performed remotely.
Step 1: Identify Target: Identify a Drupal website using a vulnerable version of the CCK Comment Reference module (5.x before 5.x-1.2 or 6.x before 6.x-1.3).
Step 2: Locate Autocomplete Path: Determine the autocomplete path used by the CCK Comment Reference module. This is typically a URL endpoint designed to provide comment suggestions.
Step 3: Craft Malicious Request: Construct a specially crafted HTTP request to the autocomplete path. The request will likely include parameters to search for specific comments or comment data.
Step 4: Bypass Access Controls: The crafted request bypasses the intended access restrictions due to the module's flawed authorization logic.
Step 5: Retrieve Sensitive Comments: The server responds with the requested comment data, including content that should be restricted based on user permissions. The attacker can now read the comments.
The vulnerability stems from a flaw in how the CCK Comment Reference module handles access control checks when processing requests through its autocomplete path. The module fails to properly validate user permissions before providing comment data via the autocomplete functionality. This allows unauthenticated users to query the autocomplete endpoint and retrieve comments that they should not have access to. The root cause is a missing or insufficient authorization check within the module's code, specifically related to the handling of comment retrieval through the autocomplete feature. This is not a buffer overflow or race condition but rather a logic flaw in the access control implementation.
While no specific APTs are definitively linked to this vulnerability, it is likely exploited by a wide range of actors, including opportunistic attackers and those seeking to gather information for further attacks. This vulnerability is not listed on the CISA KEV at this time, but given its potential for information disclosure, it could be a target for future inclusion.
Monitor web server logs for suspicious activity related to the autocomplete path of the CCK Comment Reference module (e.g., unusual request patterns, requests from unexpected IP addresses).
Analyze HTTP requests for the autocomplete path, looking for unusual parameters or requests that attempt to retrieve sensitive comment data.
Implement Web Application Firewall (WAF) rules to block or filter suspicious requests to the autocomplete path.
Monitor for unauthorized access attempts to comments or comment data.
Use file integrity monitoring to detect any unauthorized changes to the CCK Comment Reference module files.
Upgrade the CCK Comment Reference module to a patched version (5.x-1.2 or later, or 6.x-1.3 or later). This is the primary and most effective remediation step.
Review and verify the access control configurations for the CCK Comment Reference module to ensure that they are correctly implemented and restrict access to sensitive comment data.
Implement a Web Application Firewall (WAF) to filter malicious requests.
Regularly scan the Drupal installation for known vulnerabilities.
Apply the latest security patches for Drupal core and all installed modules.
Review and harden the web server configuration to mitigate potential attack vectors.