Ajax Search Lite < 4.11.1, Pro < 4.26.2 - Reflected Cross-Site Scripting

The Ajax Search Lite WordPress plugin before 4.11.1, Ajax Search Pro WordPress plugin before 4.26.2 does not sanitise and escape a parameter before outputting it back in a response of an AJAX action, leading to a Reflected Cross-Site Scripting which could be used against high privilege users such as admin