CVE-2021-28423 describes multiple SQL Injection vulnerabilities in the Teachers Record Management System versions 1.0 through 2.1. These vulnerabilities allow remote authenticated users to execute arbitrary SQL commands by manipulating specific parameters in the web application. Specifically, the 'editid' GET parameter in the files edit-subjects-detail.php and edit-teacher-detail.php, as well as the 'searchdata' POST parameter in search.php, are vulnerable. SQL Injection occurs when user-supplied input is improperly sanitized before being incorporated into SQL queries, enabling attackers to alter the intended query logic. In this case, the attacker must be authenticated, which means they need valid credentials to access the system. Once authenticated, they can exploit these injection points to execute arbitrary SQL commands, potentially leading to unauthorized data access, data modification, or even complete compromise of the backend database. The lack of a CVSS score indicates that this vulnerability has not been formally scored, but the technical details confirm it is a classic SQL Injection flaw affecting multiple input vectors within the application. No patches or vendor information are provided, and there are no known exploits in the wild as of the published date. The vulnerability affects multiple versions of the Teachers Record Management System, a specialized application used for managing teacher records, subjects, and related educational data.

For European organizations, especially educational institutions or government bodies managing teacher records, this vulnerability poses a significant risk. Exploitation could lead to unauthorized disclosure of sensitive personal data such as teacher identities, qualifications, schedules, and potentially student-related information if stored in the same system. Data integrity could also be compromised, allowing attackers to alter records, which may disrupt administrative processes or lead to misinformation. The requirement for authentication limits the attack surface to insiders or users with valid credentials, but this does not eliminate the risk, as insider threats or compromised accounts could be leveraged. Additionally, successful exploitation could enable attackers to escalate privileges or pivot to other systems within the network, increasing the overall impact. Given the critical nature of educational data and the regulatory environment in Europe (e.g., GDPR), unauthorized access or data breaches could result in legal penalties, reputational damage, and operational disruptions.

To mitigate this vulnerability, European organizations using the Teachers Record Management System should first verify if vendor patches or updates are available and apply them promptly. In the absence of official patches, organizations should implement input validation and parameterized queries (prepared statements) to sanitize all user inputs, particularly the 'editid' GET parameter and the 'searchdata' POST parameter. Conduct a thorough code review and penetration testing focused on SQL Injection vectors within the application. Employ Web Application Firewalls (WAFs) configured to detect and block SQL Injection attempts targeting these parameters. Limit user privileges strictly on a need-to-access basis to reduce the risk from authenticated users. Monitor logs for unusual database queries or errors indicative of injection attempts. Additionally, implement multi-factor authentication (MFA) to reduce the risk of credential compromise. Regularly back up databases and ensure backups are secure to enable recovery in case of data tampering. Finally, provide security awareness training to users to recognize phishing or social engineering attempts that could lead to credential theft.