CVE-2008-6749 in FlexPHPDirectory
Summary
by MITRE
Multiple SQL injection vulnerabilities in admin/usercheck.php in FlexPHPDirectory 0.0.1, when magic_quotes_gpc is disabled, allow remote attackers to execute arbitrary SQL commands via the (1) checkuser and (2) checkpass parameters.
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Analysis
by VulDB Data Team • 06/29/2025
The vulnerability identified as CVE-2008-6749 represents a critical SQL injection flaw within the FlexPHPDirectory 0.0.1 web application, specifically targeting the admin/usercheck.php script. This vulnerability arises from insufficient input validation and sanitization mechanisms that fail to properly escape or filter user-supplied data before incorporating it into SQL query constructs. The flaw is particularly severe because it occurs in the administrative authentication component of the application, which handles user credential verification processes. The vulnerability affects systems where the PHP configuration parameter magic_quotes_gpc is disabled, a common configuration in many production environments where this security feature has been deprecated and removed in modern PHP versions.
The technical exploitation of this vulnerability occurs through two distinct parameter injection points within the usercheck.php script. Attackers can manipulate the checkuser parameter to inject malicious SQL code that bypasses authentication mechanisms and potentially gains unauthorized access to administrative functions. Similarly, the checkpass parameter allows for credential-based SQL injection attacks that can be leveraged to extract sensitive user data, modify database contents, or escalate privileges within the application. The vulnerability stems from CWE-89, which classifies SQL injection as a weakness that allows attackers to manipulate database queries through untrusted input. This specific implementation flaw demonstrates poor input validation practices and violates fundamental secure coding principles that mandate proper parameterization of database queries.
The operational impact of this vulnerability extends beyond simple unauthorized access, as it provides attackers with potential persistence mechanisms within the targeted system. Successful exploitation could enable attackers to extract all user credentials stored in the database, modify or delete critical user accounts, and potentially gain complete control over the directory service. From an attacker's perspective, this vulnerability aligns with ATT&CK technique T1190, which describes exploiting vulnerabilities in web applications to gain initial access. The attack surface is particularly concerning because it targets the authentication layer, which serves as the primary gateway for administrative access and user management functions. Organizations running this vulnerable version of FlexPHPDirectory face significant risk of data breaches, unauthorized modifications to directory entries, and potential lateral movement within their network infrastructure.
Mitigation strategies for this vulnerability must address both immediate remediation and long-term architectural improvements. The primary fix involves implementing proper input validation and parameterized queries throughout the application code, particularly in the user authentication components. Organizations should disable magic_quotes_gpc and implement comprehensive input sanitization routines that properly escape special characters before database insertion. The recommended approach includes adopting prepared statements and parameterized queries as per OWASP secure coding guidelines, which directly addresses the underlying CWE-89 vulnerability. Additionally, implementing proper access controls, input length restrictions, and regular security code reviews can prevent similar issues in future development cycles. Network-based protections such as web application firewalls and intrusion detection systems can provide additional layers of defense against exploitation attempts, while regular vulnerability assessments and penetration testing should be conducted to identify and remediate similar weaknesses in the application stack.