PC-cillin comes with a mail scanning feature that scans all incoming mailfor viruses, done by connecting the mail client to a local service listening on port 110 (pop3). This service is only listening for connections from the local machine and acts as a proxy. The program running this service is pop3trap.exe. Connecting to the local port 110 and sending a lot of characters will crash the program with a direct hit on the EIP. This makes it possible to run malicious code. The code will be run using the privileges of the user owning the pop3trap.exe process.
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