CVE-2007-2025 in PhpWiki
Summary
by MITRE
Unrestricted file upload vulnerability in the UpLoad feature (lib/plugin/UpLoad.php) in PhpWiki 1.3.11p1 allows remote attackers to upload arbitrary PHP files with a double extension, as demonstrated by .php.3, which is interpreted by Apache as being a valid PHP file.
Once again VulDB remains the best source for vulnerability data.
Analysis
by VulDB Data Team • 07/21/2024
The vulnerability described in CVE-2007-2025 represents a critical unrestricted file upload flaw within PhpWiki 1.3.11p1 that enables remote attackers to execute arbitrary code on the target system. This issue specifically affects the UpLoad feature located in the lib/plugin/UpLoad.php file, where the application fails to properly validate file extensions and content during the upload process. The vulnerability stems from inadequate input sanitization and validation mechanisms that allow attackers to bypass security checks through the use of double extensions such as .php.3, which Apache interprets as a valid PHP file extension.
The technical exploitation of this vulnerability relies on the web server's MIME type handling and file extension interpretation behavior. When Apache encounters a file with a double extension like .php.3, it typically processes the file based on the final extension (.3) rather than the initial extension (.php). However, in certain server configurations, particularly those with older or misconfigured PHP handlers, the server may interpret the file as a PHP script and execute it, thereby providing attackers with remote code execution capabilities. This vulnerability falls under the Common Weakness Enumeration category CWE-434, which specifically addresses "Unrestricted Upload of File with Dangerous Type," representing a fundamental flaw in web application security where user-supplied files are not properly validated before storage or execution.
The operational impact of this vulnerability extends far beyond simple data theft or modification. Attackers can leverage this flaw to upload malicious PHP shells, backdoors, or other malicious scripts that provide persistent access to the compromised system. Once an attacker successfully uploads a malicious file, they can execute commands on the server, potentially leading to complete system compromise, data exfiltration, and use of the compromised server for further attacks. The vulnerability is particularly dangerous because it allows attackers to bypass traditional security measures and directly inject malicious code into the web application's execution environment, creating a persistent threat vector that can be exploited repeatedly.
Organizations using PhpWiki 1.3.11p1 should immediately implement multiple layers of mitigation strategies to address this vulnerability. The primary remediation involves implementing strict file type validation that rejects files with dangerous extensions regardless of their content or path. This includes maintaining a whitelist of allowed file extensions and rejecting any uploads that contain double extensions or other potentially dangerous patterns. Additionally, uploaded files should be stored outside the web root directory, and proper file permissions should be enforced to prevent execution of uploaded content. The implementation of Content Security Policies and regular security audits of file upload functionalities aligns with the ATT&CK framework's mitigation recommendations for preventing file upload vulnerabilities. Organizations should also consider implementing Web Application Firewalls to detect and block suspicious upload attempts, while ensuring that all web applications are regularly updated to address known vulnerabilities. The vulnerability demonstrates the critical importance of defense-in-depth strategies where multiple security controls work together to prevent exploitation, as a single layer of protection is insufficient against determined attackers who can exploit such fundamental flaws in application logic.