The Math.random function in the JavaScript implementation in Mozilla Firefox 3.5.10 through 3.5.11, 3.6.4 through 3.6.8, and 4.0 Beta1 uses a random number generator that is seeded only once per document object, which makes it easier for remote attackers to track a user, or trick a user into acting upon a spoofed pop-up message, by calculating the seed value, related to a "temporary footprint" and an "in-session phishing attack." NOTE: this vulnerability exists because of an incorrect fix for CVE-2008-5913.