The Registrations For The Events Calendar plugin for WordPress is vulnerable to SQL Injection via JSON keys in the 'standard' parameter hand

The Registrations For The Events Calendar plugin for WordPress is vulnerable to SQL Injection via JSON keys in the 'standard' parameter handled by the rtec_records_edit AJAX action in versions up to and including 3.2. The handler decodes attacker-controlled JSON from $_POST['standard'] and uses the JSON array keys directly as column identifiers in the SET clause of an UPDATE statement built inside RTEC_Db_Admin::update_entry(). Only esc_sql() (mysqli_real_escape_string) is applied to the identifier; that function escapes quotes, backslashes, and a few control characters but does not escape spaces, equals signs, parentheses, or hyphens, so an attacker can break out of the identifier context and inject subqueries (terminated with a SQL comment). This makes it possible for authenticated attackers, with Contributor-level access and above who can edit the targeted event, to append additional SQL queries into already existing queries that can be used to extract sensitive information from the database.