A method for controlling exposure of sensitive data though a logging system is provided. The method comprises: upon receiving a request by the request handler, determining sensitive data as part of the request by applying a rule, converting the data into a transformed format, and registering the data together with a related data field label with a log handler. Then, upon receiving by the log handler a log entry, converting each expression of the log entry into the transformed format, and comparing each transformed expression with each of the sensitive data in the transformed format. Upon determining a match of one of the transformed expressions with one of the sensitive data in the transformed format, the method comprises issuing an alert indicating that the log entry comprises sensitive data.