METHOD AND SYSTEM FOR MONITORING FOR AND BLOCKING FRAUDULENT ATTEMPTS TO LOG INTO REMOTE SERVICES USING LIST VALIDATION ATTACKS

Certain aspects of the present disclosure provide techniques for monitoring for fraudulent login attempts to remote services through an application. The method generally includes receiving a request to connect an application to a remote service. A login attempt counter tracking a number of attempts by a user to connect the application to one or more remote services is incremented. Based on determining that the login attempt counter is less than a maximum number of login attempts predicted to correspond to legitimate login activity in the application, the first username is compared to a second username included in a previous request. A distance is calculated between the first username and the second username, and one or more actions are taken to process the request based on determining whether the calculated distance exceeds a maximum predicted distance between usernames in successive requests that corresponds to legitimate login activity.