Android Smudge Attack Prevention Techniques

Graphical patterns are widely used for authentication in touch screen phones. When a user enters a pattern on a touch screen, epidermal oils of his skin leave oily residues on screen called smudge. Attackers can forensically retrieve this smudge which can help them to deduce the unlock pattern. In this paper we analyze some existing techniques and propose new techniques to prevent this attack. We propose Split pattern, Wheel lock, Random PIN lock and Temporal lock to reduce or prevent smudge attack. Usability and shoulder surfing resistance were also considered while designing these techniques. This paper explains how the proposed techniques are effective against smudge attacks.