Systems and methods for authenticating a user, the method including receiving an image of a user of a device, identifying a first facial descriptor of the user from the received image and from previously captured images of the user, and determining a difference between the first facial descriptor from the received image and that from the previously captured images. The method further includes identifying a second facial descriptor of a non-user from the previously captured images of the user, and applying facial recognition to images stored in a plurality of second social networking profiles associated with a first social networking profile of the user to identify the second facial descriptor from the images stored in the second social networking profiles. Based on the difference and the second facial descriptor, the user may be authenticated.