Abstract. Phishing, or web spoofing, is a growing problem: the Anti-Phishing Working Group (APWG) received almost 14,000 unique phishing reports in August 2005, a 56 % jump over the number of reports in December 2004 [3]. $150,000 [17]. For financial institutions, phishing is a particularly insidious problem, since trust forms the foundation for customer relationships, and phishing attacks undermine confidence in an institution. Phishing attacks succeed by exploiting a user’s inability to distinguish legitimate sites from spoofed sites. Prior research focuses on assisting the user in making this distinction, but they require the user to make the right security decision every time. A single mistake results in a total compromise of the user’s...