TinyMCE Thumbnail Gallery: Path Traversal Vulnerability (CVE-2012-20002)

The TinyMCE Thumbnail Gallery plugin for WordPress contains a path traversal vulnerability (CVE-2012-20002) in the download-image.php script. This vulnerability enables unauthenticated, remote attackers to bypass directory restrictions and access sensitive files stored on the underlying web server. By providing malicious input to the 'href' parameter, an attacker can traverse the file system to retrieve critical files such as wp-config.php, which contains database credentials and other environment secrets. This vulnerability is significant as it provides a direct path to credential exfiltration and potential secondary exploitation of the WordPress database. The Shadowserver Foundation reported observing in-the-wild exploitation of this vulnerability as early as October 2023.

Attack Chain

1. Attacker performs reconnaissance on a target WordPress site to identify the use of the vulnerable TinyMCE Thumbnail Gallery plugin.
2. Attacker crafts an HTTP GET request targeting the path /wp-content/plugins/tinymce-thumbnail-gallery/php/download-image.php.
3. Attacker injects path traversal sequences (e.g., ../../../../) into the 'href' parameter of the request.
4. The vulnerable script fails to sanitize the 'href' input and processes the request using the provided directory traversal sequences.
5. The web server process reads the target file from the file system, such as wp-config.php.
6. The server returns the contents of the requested file in the HTTP response body to the attacker.
7. Attacker parses the returned file to extract sensitive database credentials or other configuration data.

Impact

Successful exploitation allows unauthenticated attackers to read sensitive files on the server. If the target file is wp-config.php, the attacker gains access to database connection strings, database usernames, and passwords. This exposure facilitates unauthorized access to the application data, potentially leading to full site compromise, data exfiltration, or further persistence within the server environment.

Recommendation

• Update the TinyMCE Thumbnail Gallery plugin to version 1.1.0 or later immediately to address CVE-2012-20002.
• Deploy the Sigma rule provided in this brief to monitor for path traversal attempts targeting the download-image.php script.
• Audit access logs for previous GET requests to /php/download-image.php containing ".." sequences, which may indicate past exploitation attempts.