CVE-2006-4609 in PHPprojekt
Summary
by MITRE
** DISPUTED ** Multiple PHP remote file inclusion vulnerabilities in the Content Management module ("Content manager") for PHProjekt 0.6.1, when register_globals is enabled, allow remote attackers to execute arbitrary PHP code via the path_pre parameter in (1) cm_lib.inc.php, (2) doc/br.edithelp.php, (3) doc/de.edithelp.php, (4) doc/ct.edithelp.php, (5) userrating.php, and (6) listing.php, a different set of vectors than CVE-2006-4204. NOTE: a third-party researcher has disputed the impact of the cm_lib.inc.php vector, stating that it is limited to local file inclusion. CVE analysis as of 20060905 concurs, although use of ftp URLs is also possible. The remaining five vectors have also been disputed by the same third party, stating that the path_pre variable is initialized before it is used.
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Analysis
by VulDB Data Team • 08/08/2024
The vulnerability described in CVE-2006-4609 represents a critical remote code execution risk within the PHProjekt Content Management module version 0.6.1, specifically when the PHP configuration parameter register_globals is enabled. This configuration setting allows external input to be automatically imported into the global scope, creating dangerous conditions for code injection attacks. The vulnerability affects multiple files within the application's documentation and content management components, including cm_lib.inc.php, various help documentation files, userrating.php, and listing.php, making it a widespread issue across the module's functionality.
The technical flaw stems from improper input validation and parameter handling within the Content Manager module, where the path_pre parameter is directly incorporated into file inclusion operations without adequate sanitization. When register_globals is enabled, attacker-controlled input can be seamlessly integrated into the application's global namespace, enabling malicious actors to manipulate the path_pre variable through HTTP parameters. This creates a remote file inclusion vulnerability that allows arbitrary PHP code execution, as the application processes the attacker's input as part of the file inclusion mechanism. The vulnerability operates under CWE-98, which specifically addresses improper file inclusion, and aligns with ATT&CK technique T1190 for exploiting remote file inclusion vulnerabilities.
The operational impact of this vulnerability extends beyond simple code execution, as it provides attackers with complete control over the affected system. An attacker could potentially upload malicious files, execute system commands, access sensitive data, or establish persistent backdoors within the application environment. The fact that multiple vectors exist across different files increases the attack surface significantly, as each endpoint represents a potential entry point for exploitation. The vulnerability's classification as a remote code execution issue places it in the highest severity category, as it enables attackers to completely compromise the targeted system without requiring local access or authentication.
The disputed nature of certain vectors within this CVE highlights the complexity of vulnerability analysis and the importance of thorough testing. The third-party researcher's findings regarding cm_lib.inc.php indicate that this particular vector is limited to local file inclusion rather than remote code execution, suggesting that the original assessment may have been overly broad. However, the analysis of the remaining five vectors has also been disputed, with the researcher claiming that the path_pre variable is properly initialized before use, which would prevent exploitation. This dispute underscores the need for careful validation of vulnerability claims and the importance of understanding the specific conditions under which vulnerabilities actually exist, as misclassification can lead to either false positives or false negatives in security assessments.
While the vulnerability demonstrates a clear path to remote code execution under specific conditions, the actual exploitation requires the presence of register_globals=on in the PHP configuration, which is considered a deprecated and dangerous setting by modern security standards. The security community has long advised against using register_globals due to its inherent risks, and most modern PHP applications avoid this configuration entirely. Organizations should ensure that all PHP applications are configured with register_globals=off to prevent this class of vulnerabilities from being exploited. Additionally, implementing proper input validation, using secure coding practices, and employing web application firewalls can provide additional layers of protection against similar remote file inclusion attacks.
The vulnerability analysis also reveals important lessons about the importance of proper parameter handling and input validation in web applications. Modern security practices emphasize the principle of least privilege and input sanitization, where all external inputs are treated as potentially malicious and validated before use. This vulnerability demonstrates how a single configuration error in PHP can lead to catastrophic consequences, highlighting the need for comprehensive security reviews and the implementation of secure coding standards throughout the development lifecycle. The fact that this vulnerability was present in a widely-used content management system underscores the importance of regular security updates and the need for organizations to maintain awareness of known vulnerabilities in their software components.