CVE-2008-4632 in Kure
Summary
by MITRE
Multiple directory traversal vulnerabilities in index.php in Kure 0.6.3, when magic_quotes_gpc is disabled, allow remote attackers to read and possibly execute arbitrary local files via a .. (dot dot) in the (1) post and (2) doc parameters.
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Analysis
by VulDB Data Team • 11/08/2024
The vulnerability identified as CVE-2008-4632 represents a critical directory traversal flaw in the Kure 0.6.3 web application, specifically within the index.php script. This vulnerability stems from inadequate input validation mechanisms that fail to properly sanitize user-supplied parameters before processing them in file system operations. The flaw manifests when the PHP configuration parameter magic_quotes_gpc is disabled, which removes the automatic escaping of special characters that would normally prevent malicious input from being interpreted as directory traversal sequences.
The technical exploitation occurs through manipulation of two specific parameters named post and doc within the index.php script. Attackers can craft malicious requests containing .. (dot dot) sequences in these parameters to navigate outside the intended directory boundaries and access arbitrary local files on the server. This vulnerability falls under CWE-22, which specifically addresses Improper Limitation of a Pathname to a Restricted Directory, commonly known as Path Traversal. The flaw enables attackers to potentially read sensitive files such as configuration files, database credentials, or other system resources that should remain inaccessible to remote users.
The operational impact of this vulnerability is severe as it allows remote attackers to execute arbitrary file read operations without authentication, potentially leading to information disclosure and system compromise. When magic_quotes_gpc is disabled, the application becomes particularly vulnerable because the server no longer automatically escapes special characters, leaving the application to handle input sanitization entirely through its own logic. This creates a window of opportunity for attackers to exploit the lack of proper input validation, potentially leading to complete system compromise if sensitive files containing database credentials, application secrets, or system configurations are accessible through the traversal mechanism.
The attack vector for this vulnerability operates entirely through HTTP requests targeting the vulnerable index.php script, making it particularly dangerous as it requires no privileged access or local system knowledge to exploit. The vulnerability is consistent with ATT&CK technique T1083, which involves discovering system information through directory traversal attacks. Organizations running Kure 0.6.3 with magic_quotes_gpc disabled should immediately implement mitigations including input validation, parameter sanitization, and restricting file access permissions. The most effective remediation involves implementing proper input validation routines that reject or sanitize directory traversal sequences, ensuring that all user-supplied parameters are validated against a whitelist of acceptable values before being processed in file system operations. Additionally, enabling magic_quotes_gpc or implementing equivalent protection mechanisms at the application level provides defense in depth against similar vulnerabilities in future deployments.