The remote host is vulnerable to a buffer overflow.
The remote host is running Citadel, a messaging software for Unix systems. There is a buffer overflow vulnerability in the remote version of this software that may be exploited by an attacker to execute arbitrary commands on the remote host. The flaw stems from a flaw when handling user-supplied 'RCPT TO' data. The application cannot handle 'RCPT TO' strings that are greater than 4096 bytes.
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