CVE-2018-6577 in JEXTN Membership
Summary
by MITRE
SQL Injection exists in the JEXTN Membership 3.1.0 component for Joomla! via the usr_plan parameter in a view=myplans&task=myplans.usersubscriptions request.
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Analysis
by VulDB Data Team • 06/15/2025
The vulnerability CVE-2018-6577 represents a critical SQL injection flaw within the JEXTN Membership component version 3.1.0 for Joomla! platforms. This security weakness specifically manifests through the usr_plan parameter within the request structure view=myplans&task=myplans.usersubscriptions, creating an exploitable pathway for malicious actors to manipulate database queries. The vulnerability resides in the component's insufficient input validation mechanisms, allowing attackers to inject malicious SQL code that bypasses normal authentication and authorization controls. Such a flaw fundamentally undermines the integrity of the underlying database system and can lead to complete system compromise when exploited effectively.
The technical implementation of this vulnerability stems from improper sanitization of user-supplied input within the JEXTN Membership component. When the usr_plan parameter is processed without adequate filtering or parameterization, the application constructs SQL queries that directly incorporate user-provided data into the database execution context. This primitive approach to input handling aligns with CWE-89, which categorizes SQL injection as a persistent weakness where untrusted data is embedded into SQL commands without proper escaping or parameterization. The vulnerability operates at the application layer and requires minimal privileges to exploit, making it particularly dangerous as it can be leveraged by both authenticated and unauthenticated attackers depending on the specific implementation details of the affected Joomla! installation.
The operational impact of CVE-2018-6577 extends far beyond simple data theft, encompassing complete database compromise and potential system takeover. Attackers can leverage this vulnerability to extract sensitive information including user credentials, membership details, and potentially administrative access credentials stored within the database. The attack surface is particularly concerning because the vulnerability affects a widely deployed Joomla! component, meaning that numerous websites and organizations using this membership system could be simultaneously compromised. Additionally, successful exploitation could enable attackers to modify or delete database records, inject malicious content, or establish persistent backdoors within the affected systems. The vulnerability also aligns with ATT&CK technique T1071.004 which covers application layer protocol manipulation, and T1213.002 which addresses data from information repositories.
Mitigation strategies for CVE-2018-6577 must address both immediate remediation and long-term security improvements within the affected Joomla! environment. The primary recommendation involves upgrading the JEXTN Membership component to a patched version that properly implements parameterized queries and input validation. Organizations should also implement proper input sanitization techniques including the use of prepared statements with parameterized queries to prevent similar vulnerabilities from occurring in the future. Network-level protections such as web application firewalls can provide additional defense-in-depth measures, though they should not be considered a substitute for proper code-level fixes. Security monitoring should include detection of unusual database query patterns and parameter values that might indicate exploitation attempts. The vulnerability serves as a reminder of the critical importance of regular security updates and the implementation of secure coding practices that prevent injection vulnerabilities through proper input validation and parameterized query construction.