This indicates an attack attempt against an Integer Overflow vulnerability in several Mozilla products.
The vulnerability is the result of an integer overflow. It can be exploited by a remote attacker to execute arbitrary code on vulnerable systems.
Mozilla Foundation Firefox prior to 3.6.18
Mozilla Foundation SeaMonkey 2.1 and prior.
Mozilla Foundation Thunderbird prior to 3.1.11
System Compromise: Remote attackers can gain control of vulnerable systems.
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