source: https://www.securityfocus.com/bid/62/info

There exists a buffer overflow in the Stalker Internet Mail Server version 1.6. If you connect to the SMTP port and issue a HELO command with a large string (several hundred bytes) for a hostname the server, and possibly MacOS, will crash.

220-Stalker Internet Mail Server V.1.6 is ready.
220 ESMTP is spoken here.
HELO
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