The remote host may give an attacker information useful for future attacks.
The remote host is running the mIRC chat client. A vulnerability has been reported in the mIRC implementation of the DCC protocol. Reportedly, when a DCC connection is initiated, the command '100 testing' will cause the mIRC server to respond with the user's current nick. Exploitation of this vulnerability may aid an attack in further intelligent attacks, or help an attempt at social engineering.
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