This indicates an attack attempt to exploit a Buffer Overflow vulnerability in Macromedia JRun web server.
The vulnerability is due to an improper boundary check condition in the application when handling overly long URI. A remote attacker may be able to exploit this to execute arbitrary code within the context of the application, via a crafted HTTP request.
Macromedia JRun 4.0 SP1a
Macromedia JRun 4.0 SP1
Macromedia JRun 4.0 build 61650
Macromedia JRun 4.0
System Compromise: Remote attackers can gain control of vulnerable systems.
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