Methods and systems described herein authenticate a user and help secure transaction. A display screen presents images that are difficult for malware to recognize but a person can recognize. In at least one embodiment, a person communicates transaction information using visual images received from the service provider system. In at least one embodiment, a user selects a sequence of visual images as a means of authenticating the user and logging into a financial account or other corporate account.
In some embodiments, methods and systems are provided for determining whether to grant access, by generating and displaying visual images on a screen that the user can recognize, and select. In an embodiment, a user presses his or her finger or fingers on a display screen to select images as a method for authenticating and protecting communication from malware.
In an embodiment, non-determinism in hardware helps unpredictably vary the image selected, the image location, generate noise in the image, or change the shape or texture of the image. In some embodiments, visual image authentication helps Alice and Bob detect if Eve has launched a man-in-the-middle attack on their key exchange.