CVE-2021-47918 in Simple CMS
Summary
by MITRE • 02/01/2026
Simple CMS 2.1 contains a remote SQL injection vulnerability that allows privileged attackers to inject unfiltered SQL commands in the users module. Attackers can exploit unvalidated input parameters in the admin.php file to compromise the database management system and web application.
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Analysis
by VulDB Data Team • 02/12/2026
The vulnerability identified as CVE-2021-47918 affects Simple CMS version 2.1 and represents a critical remote SQL injection flaw that can be exploited by authenticated attackers with privileged access. This vulnerability resides within the users module of the content management system and specifically targets the admin.php file where input parameters are not properly validated or sanitized. The flaw allows malicious actors to inject arbitrary SQL commands directly into the database management system through the web application interface, potentially enabling complete database compromise and unauthorized access to sensitive user information.
The technical implementation of this vulnerability stems from inadequate input validation mechanisms within the application's administrative interface. When privileged users interact with the admin.php file, the system fails to properly filter or escape user-supplied input before incorporating it into SQL query constructions. This lack of proper sanitization creates an exploitable entry point where attackers can manipulate database queries through carefully crafted payloads. The vulnerability is classified as a remote SQL injection according to CWE-89, which specifically addresses improper neutralization of special elements used in SQL commands. The attack vector requires authentication as a privileged user, making it a privilege escalation vulnerability that can be leveraged to gain deeper access to the system's data infrastructure.
The operational impact of this vulnerability extends beyond simple data theft, as successful exploitation can result in complete database compromise, unauthorized user account manipulation, and potential lateral movement within the affected network infrastructure. Attackers can leverage this vulnerability to extract sensitive user credentials, personal information, and potentially gain access to other system resources that rely on the compromised database. The vulnerability affects the confidentiality, integrity, and availability of the web application and underlying database systems, creating significant risk for organizations relying on Simple CMS for content management. According to ATT&CK framework, this vulnerability maps to T1190 - Exploit Public-Facing Application and T1078 - Valid Accounts, as it requires legitimate privileged access to exploit effectively while targeting publicly accessible administrative interfaces.
Organizations affected by CVE-2021-47918 should prioritize immediate remediation through official security patches provided by the Simple CMS vendor, as the vulnerability allows for complete database compromise when exploited by authenticated attackers. Additional mitigations include implementing proper input validation and output encoding mechanisms, enforcing principle of least privilege for administrative accounts, and deploying web application firewalls to detect and block malicious SQL injection attempts. Security monitoring should focus on unusual database query patterns and unauthorized administrative access attempts. The vulnerability demonstrates the critical importance of proper input validation in web applications and highlights the need for regular security assessments of content management systems. Organizations should also consider implementing database activity monitoring and regular penetration testing to identify similar vulnerabilities in their infrastructure, as this flaw represents a common attack pattern that can be exploited across various web applications lacking proper security controls.