This indicates an attack attempt against a Memory Corruption vulnerability in several Mozilla products.
The vulnerability is due an error when handling interactions with certain event handler. It can be exploited by a remote attacker to execute arbitrary code on vulnerable systems.
Mozilla Thunderbird 8.0
Mozilla SeaMonkey 2.5
Mozilla Firefox 8.0.1
Mozilla Firefox 8.0
Mozilla Firefox 7
System Compromise: Remote attackers can gain control of vulnerable systems.
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