CVE-2011-4921 in e107
Summary
by MITRE
SQL injection vulnerability in usersettings.php in e107 0.7.26, and possibly other versions before 1.0.0, allows remote attackers to execute arbitrary SQL commands via the username parameter.
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Analysis
by VulDB Data Team • 07/11/2019
The vulnerability identified as CVE-2011-4921 represents a critical SQL injection flaw discovered in the usersettings.php script of the e107 content management system version 0.7.26 and potentially affecting earlier versions up to but not including 1.0.0. This vulnerability resides within the user management functionality of the platform, specifically in how the application processes the username parameter submitted through web forms. The flaw stems from insufficient input validation and sanitization mechanisms that fail to properly escape or filter user-supplied data before incorporating it into database queries. Attackers can exploit this weakness by crafting malicious SQL commands within the username parameter, which then get executed by the underlying database engine with the privileges of the web application's database user account.
The technical exploitation of this vulnerability occurs when an attacker submits a specially crafted username value containing SQL payload characters and commands. The vulnerable e107 application directly incorporates this unvalidated input into SQL query construction without proper parameterization or escaping, creating an environment where arbitrary SQL commands can be executed. This type of vulnerability maps directly to CWE-89, which defines SQL injection as the improper handling of user-supplied data in SQL queries. The attack vector is particularly dangerous because it allows remote code execution capabilities, potentially enabling attackers to extract sensitive data, modify database contents, or even escalate privileges within the application environment.
The operational impact of this vulnerability extends beyond simple data theft, as successful exploitation can lead to complete system compromise and unauthorized access to user accounts, personal information, and potentially the entire database infrastructure. The vulnerability affects not just individual user records but can provide attackers with access to all data stored within the e107 database, including administrative credentials, user authentication details, and application configuration settings. This represents a severe risk to organizations relying on e107 for their web presence, as it can result in data breaches, service disruption, and potential regulatory compliance violations. The vulnerability's remote exploitability means that attackers do not need physical access to the server and can target the application from anywhere on the internet.
Mitigation strategies for CVE-2011-4921 should prioritize immediate patching of affected e107 installations to version 1.0.0 or later where the vulnerability has been addressed through proper input validation and parameterized query implementation. Organizations should also implement web application firewalls to detect and block malicious SQL injection attempts, enforce strict input validation at all application entry points, and apply the principle of least privilege to database accounts used by the web application. Additionally, regular security auditing and penetration testing should be conducted to identify similar vulnerabilities in other application components. The remediation efforts should align with ATT&CK framework techniques related to credential access and defense evasion, as the vulnerability could enable attackers to establish persistent access through compromised user accounts and database credentials, making proper patch management and access control critical defensive measures.