The JavaScript engine in Mozilla Firefox before 2.0.0.12, Thunderbird before 2.0.0.12, and SeaMonkey before 1.1.8 allows remote attackers to cause a denial of service (crash) and possibly trigger memory corruption via (1) a large switch statement, (2) certain uses of watch and eval, (3) certain uses of the mousedown event listener, and other vectors.
Weaknesses in this category are related to improper management of system resources.