js/src/jstracer.cpp in the Just-in-time (JIT) JavaScript compiler (aka TraceMonkey) in Mozilla Firefox 3.5 before 3.5.1 allows remote attackers to execute arbitrary code via certain use of the escape function that triggers access to uninitialized memory locations, as originally demonstrated by a document containing P and FONT elements.

Array index error in the (1) dtoa implementation in dtoa.c (aka pdtoa.c) and the (2) gdtoa (aka new dtoa) implementation in gdtoa/misc.c in libc, as used in multiple operating systems and products including in FreeBSD 6.4 and 7.2, NetBSD 5.0, OpenBSD 4.5, Mozilla Firefox 3.0.x before 3.0.15 and 3.5.x before 3.5.4, K-Meleon 1.5.3, SeaMonkey 1.1.8, and other products, allows context-dependent attackers to cause a denial of service (application crash) and possibly execute arbitrary code via a large precision value in the format argument to a printf function, which triggers incorrect memory allocation and a heap-based buffer overflow during conversion to a floating-point number.

The Math.random function in the JavaScript implementation in Mozilla Firefox 3.5.x before 3.5.10 and 3.6.x before 3.6.4, and SeaMonkey before 2.0.5, uses a random number generator that is seeded only once per browser session, 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."