Implementations of the present disclosure relate to security testing based on user request. According to the method, a first request for a target application is received from a first user. A first malicious request is generated by modifying the first request, wherein the first malicious is associated with a malicious action on the target application. The first malicious request is sent to an offline instance of the target application. A first security level of the target application against the malicious action is determined based on a first response generated by the offline instance in response to the first malicious request. In other implementations, a system and a computer program product for process tracking are disclosed.