Improper Neutralization of Special Elements used in an SQL Command ('SQL Injection')
The Simple Quotation WordPress plugin through 1.3.2 does not have authorisation (and CSRF) checks in various of its AJAX actions and is lacking escaping of user data when using it in SQL statements, allowing any authenticated users, such as subscriber to perform SQL injection attacks
CWE-89 - SQL Injection
Structured Query Language (SQL) injection attacks are one of the most common types of vulnerabilities. They exploit weaknesses in vulnerable applications to gain unauthorized access to backend databases. This often occurs when an attacker enters unexpected SQL syntax in an input field. The resulting SQL statement behaves in the background in an unintended manner, which allows the possibility of unauthorized data retrieval, data modification, execution of database administration operations, and execution of commands on the operating system.