CVE-2008-6730 in FlexPHPLink
Summary
by MITRE
Multiple SQL injection vulnerabilities in admin/usercheck.php in FlexPHPLink Pro 0.0.6 and 0.0.7, when magic_quotes_gpc is disabled, allow remote attackers to execute arbitrary SQL commands via (1) the checkuser parameter (aka username field), or (2) the checkpass parameter (aka password field), to admin/index.php.
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Analysis
by VulDB Data Team • 06/29/2025
The vulnerability described in CVE-2008-6730 represents a critical SQL injection flaw affecting FlexPHPLink Pro versions 0.0.6 and 0.0.7. This vulnerability specifically targets the administrative user validation functionality within the application's usercheck.php component. The flaw occurs when the PHP configuration parameter magic_quotes_gpc is disabled, which removes the automatic escaping of special characters in GET, POST, and COOKIE data. This configuration setting is crucial for preventing many injection attacks, as it automatically escapes single quotes, double quotes, backslashes, and null bytes in user input data. When disabled, the application becomes vulnerable to malicious input manipulation that can bypass normal input sanitization mechanisms.
The technical implementation of this vulnerability involves two distinct attack vectors through the checkuser and checkpass parameters. The checkuser parameter corresponds to the username field in the administrative login interface, while the checkpass parameter maps to the password field. Attackers can craft malicious input strings that contain SQL commands designed to manipulate the database query execution flow. These malicious inputs are directly incorporated into the SQL statements without proper sanitization or parameterization, allowing attackers to inject arbitrary SQL code. The vulnerability operates at the application layer, specifically targeting the database interaction logic that validates administrative credentials, making it a classic example of improper input validation and sanitization.
The operational impact of this vulnerability is severe and multifaceted. Successful exploitation enables remote attackers to execute arbitrary SQL commands against the underlying database, potentially leading to complete database compromise. Attackers can perform read operations to extract sensitive user information, modify or delete database records, and even gain unauthorized access to administrative accounts. The vulnerability's remote nature means that attackers do not require local system access or authentication to exploit the flaw, making it particularly dangerous for web applications. This type of vulnerability falls under CWE-89, which specifically addresses SQL injection flaws, and aligns with ATT&CK technique T1190 for exploitation of remote services through SQL injection attacks. The impact extends beyond simple data theft, as attackers can potentially escalate privileges and establish persistent access to the application infrastructure.
Mitigation strategies for this vulnerability require immediate implementation of multiple defensive measures. The most critical approach involves enabling proper input validation and sanitization by either configuring magic_quotes_gpc to be enabled or implementing robust parameterized queries and prepared statements. Applications should validate all user inputs against expected formats and lengths while implementing proper escaping mechanisms for database queries. The recommended long-term solution includes upgrading to a newer version of FlexPHPLink Pro that addresses this vulnerability, as the affected versions are outdated and likely contain additional security weaknesses. Organizations should also implement web application firewalls and database activity monitoring to detect and prevent exploitation attempts. Additionally, regular security assessments and code reviews should be conducted to identify similar vulnerabilities in other application components, particularly focusing on database interaction points and input handling mechanisms that could be susceptible to injection attacks.