CVE-2006-4963 in Exponent
Summary
by MITRE
Directory traversal vulnerability in index.php in Exponent CMS 0.96.3 allows remote attackers to read and execute arbitrary local files via a .. (dot dot) sequence in the view parameter in the show_view action in the calendarmodule module, as demonstrated by executing PHP code through session files.
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Analysis
by VulDB Data Team • 07/21/2024
The vulnerability described in CVE-2006-4963 represents a critical directory traversal flaw within the Exponent CMS 0.96.3 content management system. This weakness specifically affects the calendarmodule component where the index.php script fails to properly validate user input parameters, creating an exploitable condition that allows remote attackers to manipulate file access paths. The vulnerability manifests when attackers manipulate the view parameter within the show_view action, enabling them to traverse the filesystem using the .. (dot dot) sequence commonly known as path traversal or directory traversal attacks. The flaw resides in the application's inadequate sanitization of input data, particularly within the calendar module's file inclusion mechanism.
The technical exploitation of this vulnerability follows a well-established pattern that aligns with CWE-22, which categorizes improper limitation of a pathname to a restricted directory, also known as path traversal or directory traversal. Attackers can leverage this weakness to access arbitrary local files on the server by crafting malicious URLs that include the .. sequence in the view parameter. The demonstration of the vulnerability shows how attackers can execute PHP code through session files, which represents a particularly dangerous exploitation vector since session files often contain sensitive data and may include executable code. This type of attack can lead to complete system compromise, data exfiltration, and unauthorized access to the underlying server infrastructure.
The operational impact of this vulnerability extends beyond simple file access, as it can result in full system compromise when attackers successfully execute PHP code from session files. The vulnerability affects organizations running Exponent CMS 0.96.3 installations, potentially exposing them to unauthorized access, data breaches, and system infiltration. The attack surface is particularly concerning because calendar modules often contain user-generated content and may have access to sensitive server resources. This vulnerability can be exploited without authentication, making it particularly dangerous as it allows remote attackers to gain access to server resources from any network location. The implications align with ATT&CK technique T1059.007, which covers the execution of code through PHP files, and T1566, which involves the exploitation of vulnerabilities in web applications.
Mitigation strategies for CVE-2006-4963 should prioritize immediate patching of the Exponent CMS to version 0.96.4 or later, which contains the necessary fixes for the directory traversal vulnerability. Organizations should implement input validation measures that sanitize all user-supplied parameters, particularly those used in file inclusion operations. The application should enforce strict path validation to prevent the use of directory traversal sequences and implement proper access controls to limit file system access. Network-level protections such as web application firewalls and intrusion detection systems can provide additional layers of defense. Regular security audits and vulnerability assessments should be conducted to identify similar weaknesses in other applications and components. The remediation process should also include monitoring for unauthorized access attempts and implementing proper logging mechanisms to track potential exploitation attempts. Security teams should ensure that all web applications undergo regular updates and that development practices include proper input validation and secure coding techniques to prevent similar vulnerabilities from being introduced in future releases.