The WP Maps plugin for WordPress is vulnerable to time-based blind SQL Injection via the 'location_id' parameter in all versions up to, and including, 4.9.1. This is due to the plugin's database abstraction layer (`FlipperCode_Model_Base::is_column()`) treating user input wrapped in backticks as column names, bypassing the `esc_sql()` escaping function. Additionally, the `wpgmp_ajax_call` AJAX handler (registered for unauthenticated users via `wp_ajax_nopriv`) allows calling arbitrary class methods including `wpgmp_return_final_capability`, which passes the unsanitized `location_id` GET parameter directly to a database query. This makes it possible for unauthenticated attackers to append additional SQL queries into already existing queries that can be used to extract sensitive information from the database.

The WP Maps plugin for WordPress is vulnerable to time-based blind SQL Injection via the 'location_id' parameter in all versions up to, and including, 4.9.1. This is due to the plugin's database abstraction layer (`FlipperCode_Model_Base::is_column()`) treating user input wrapped in backticks as column names, bypassing the `esc_sql()` escaping function. Additionally, the `wpgmp_ajax_call` AJAX handler (registered for unauthenticated users via `wp_ajax_nopriv`) allows calling arbitrary class methods including `wpgmp_return_final_capability`, which passes the unsanitized `location_id` GET parameter directly to a database query. This makes it possible for unauthenticated attackers to append additional SQL queries into already existing queries that can be used to extract sensitive information from the database.