NoTabNab: Protection against the "tabnabbing attack"

In recent years phishing attacks have become one of the most important problems of online security. Aza Raskin, the creative lead of Mozilla Firefox team, proposed a new type of phishing attack, "tabnabbing attack" as he names it. The attack is different from classical phishing attacks; while classical attacks rely on deception of users with a similar URL and/or content in appearance to the original site, this attack uses our memory weakness and false perception that browser tabs are immutable i.e., do not change while inactive. We develop a Firefox add-on to protect users against this attack. Our method is based on the fact that a phishing web site should change its layout radically to look like the original site. This add-on watches the open tabs and indicates whether one changes its layout, favicon and/or title to become like another site.