CVE-2004-1998 in PHP-Nuke
Summary
by MITRE
The Downloads module in Php-Nuke 6.x through 7.2 allows remote attackers to gain sensitive information via an invalid show parameter to modules.php, which reveals the full path in a PHP error message.
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Analysis
by VulDB Data Team • 06/18/2018
The vulnerability described in CVE-2004-1998 represents a classic information disclosure flaw within the Php-Nuke content management system that affected versions 6.x through 7.2. This issue resides within the Downloads module and demonstrates how improper input validation can lead to significant security implications for web applications. The vulnerability specifically manifests when an attacker crafts a malicious request containing an invalid show parameter and directs it to the modules.php endpoint, which then generates a PHP error message containing the full server path. This type of information disclosure vulnerability falls under the Common Weakness Enumeration category CWE-200, which specifically addresses information exposure through error messages that reveal system details. The flaw essentially exposes the underlying file system structure of the web server to potential attackers, providing them with critical information that could be leveraged in subsequent attacks.
The technical mechanism behind this vulnerability involves the lack of proper parameter validation within the Downloads module's handling of user input. When the show parameter contains invalid data, the system fails to properly sanitize or validate the input before processing it, resulting in a PHP error that inadvertently includes the complete file path where the application is installed. This occurs because the application does not implement proper error handling procedures that would prevent sensitive system information from being exposed to end users or attackers. The error message generation process in the affected versions of Php-Nuke does not filter or sanitize the input parameters before they are processed, allowing the full path to be rendered in the error output. This behavior aligns with ATT&CK technique T1212, which focuses on exploitation of information disclosure vulnerabilities to gather system information for further attacks.
The operational impact of this vulnerability extends beyond simple information disclosure, as it provides attackers with crucial reconnaissance data that can significantly aid in planning more sophisticated attacks against the target system. The exposed full path information can reveal directory structures, potentially indicating the presence of other files or directories that might be vulnerable to additional attacks. Attackers can use this information to craft more targeted attacks, such as directory traversal exploits or to identify the specific operating system and web server configuration. The vulnerability essentially provides a foothold for attackers to understand the system environment better, potentially enabling them to discover other weaknesses or misconfigurations within the web application or server infrastructure. Organizations running affected versions of Php-Nuke face increased risk of successful exploitation, as this information disclosure can serve as a stepping stone for more serious security breaches.
Mitigation strategies for CVE-2004-1998 primarily involve implementing proper input validation and error handling procedures within the application code. System administrators should immediately upgrade to patched versions of Php-Nuke that address this vulnerability, as the affected versions are no longer supported and likely contain additional security flaws. The recommended approach includes configuring the web application to suppress detailed error messages from being displayed to end users, implementing proper parameter validation for all input fields, and ensuring that error handling routines do not expose system path information. Organizations should also implement proper logging mechanisms to detect and respond to attempts to exploit this vulnerability, while applying the principle of least privilege to limit the exposure of sensitive system information. Additionally, network-level protections such as web application firewalls can help detect and block malicious requests attempting to exploit this vulnerability, though the most effective solution remains the immediate patching of affected systems.