Improper Neutralization of Special Elements used in an SQL Command ('SQL Injection')
The WP Email Users WordPress plugin through 1.7.6 does not escape the data_raw parameter in the weu_selected_users_1 AJAX action, available to any authenticated users, allowing them 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.