CVE-2006-4532 in YACS
Summary
by MITRE
PHP remote file inclusion vulnerability in articles/article.php in Yet Another Community System (YACS) CMS 6.6.1 and earlier allows remote attackers to execute arbitrary PHP code via a URL in the context[path_to_root] parameter.
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Analysis
by VulDB Data Team • 07/17/2024
The vulnerability identified as CVE-2006-4532 represents a critical remote file inclusion flaw within the Yet Another Community System CMS version 6.6.1 and earlier. This vulnerability exists in the articles/article.php component where the application fails to properly validate user input before incorporating it into file system operations. The flaw specifically manifests when the context[path_to_root] parameter is manipulated by an attacker to point to a remote malicious URL, enabling the execution of arbitrary PHP code on the target server. This type of vulnerability falls under the category of CWE-88, which describes improper neutralization of special elements used in an OS command, and more specifically aligns with CWE-94, representing improper execution of code. The vulnerability operates at the intersection of insecure input handling and remote code execution, making it particularly dangerous for web applications that process user-supplied data without adequate sanitization.
The operational impact of this vulnerability extends far beyond simple code execution, as it provides attackers with complete control over the affected server. Once exploited, the malicious code can be used to establish persistent backdoors, exfiltrate sensitive data, modify content, or even compromise the entire underlying infrastructure. The attack vector leverages the standard HTTP protocol to deliver malicious payloads, making it difficult to detect through traditional network monitoring. According to the MITRE ATT&CK framework, this vulnerability maps to T1059.007 for remote code execution and T1071.004 for application layer protocols, highlighting the multi-faceted nature of the threat. The vulnerability's exploitation requires minimal technical expertise, making it attractive to attackers across the spectrum from script kiddies to sophisticated threat actors.
Mitigation strategies for CVE-2006-4532 must address both immediate remediation and long-term security hardening measures. The primary fix involves implementing proper input validation and sanitization for all user-supplied parameters, particularly those used in file path operations. The application should enforce strict whitelisting of acceptable values for the path_to_root parameter or implement comprehensive URL validation to prevent external references. Additionally, the use of PHP's open_basedir directive and disabling of remote file inclusion features through the allow_url_include directive provides effective barriers against exploitation. Organizations should also implement web application firewalls to detect and block suspicious URL patterns and maintain comprehensive logging to monitor for exploitation attempts. Regular security audits and vulnerability assessments should be conducted to identify similar flaws in other components, as this vulnerability pattern is commonly found in legacy content management systems and underscores the importance of keeping CMS platforms updated to prevent exploitation of known vulnerabilities.