CVE-2011-1669 in WP Custom Pages
Summary
by MITRE
Directory traversal vulnerability in wp-download.php in the WP Custom Pages module 0.5.0.1 for WordPress allows remote attackers to read arbitrary files via ..%2F (encoded dot dot) sequences in the url parameter.
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Analysis
by VulDB Data Team • 01/30/2025
The CVE-2011-1669 vulnerability represents a critical directory traversal flaw within the WP Custom Pages module version 0.5.0.1 for WordPress, specifically affecting the wp-download.php script. This vulnerability stems from inadequate input validation and sanitization mechanisms that fail to properly handle maliciously crafted URL parameters containing encoded directory traversal sequences. The flaw enables remote attackers to bypass normal access controls and retrieve arbitrary files from the web server's file system by exploiting the ..%2F encoding pattern, which translates to the traditional ../ sequence used to navigate up directory levels in Unix-like systems.
The technical implementation of this vulnerability occurs at the application layer where user-supplied input from the url parameter is directly processed without proper validation or sanitization. When an attacker submits a request containing ..%2F sequences encoded in the URL, the application fails to properly sanitize these inputs before using them in file operations. This allows the attacker to traverse the file system hierarchy and access files that should normally be restricted, including configuration files, database credentials, and potentially sensitive system information. The vulnerability is classified under CWE-22 as "Improper Limiting of a Pathname to a Restricted Directory ('Path Traversal')" and aligns with ATT&CK technique T1213.002 for "Exploitation for Credential Access" when sensitive files are accessed.
The operational impact of this vulnerability extends beyond simple information disclosure, as it can potentially lead to complete system compromise when combined with other attack vectors. Attackers can leverage this vulnerability to access WordPress configuration files containing database credentials, plugin files that may contain additional vulnerabilities, or even system files that could reveal the underlying server architecture. The remote nature of this attack means that no local system access is required, making it particularly dangerous as it can be exploited from anywhere on the internet. This vulnerability directly violates the principle of least privilege and demonstrates a fundamental flaw in input handling within the WordPress plugin ecosystem.
Mitigation strategies for CVE-2011-1669 should focus on immediate patching of the affected WP Custom Pages module to version 0.5.0.2 or later, which contains the necessary input validation fixes. Organizations should also implement web application firewalls with rules specifically designed to detect and block directory traversal attempts, particularly those involving encoded sequences like ..%2F. Additionally, the principle of least privilege should be enforced by ensuring that web server processes operate with minimal required permissions and that sensitive files are properly protected through file system permissions. Regular security auditing of WordPress plugins and themes should be conducted to identify and remediate similar vulnerabilities, while implementing proper input validation at all entry points to prevent similar issues from occurring in other components of the web application stack.