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HeckFeckyesterday at 7:50 PM2 repliesview on HN

I used telnet to send mail via SMTP once, it's quite literally a good social protocol because it begins with a polite 'HELO'.


Replies

nativeityesterday at 10:19 PM

Is it the reply to ‘HELO’ that enables things like tarpits?

Like if my server replied with ‘HI PLEASURE TO MEET YOU 127.0.0.1 THAT NAME SOUNDS FAMILIAR ARE YOU BY CHANCE FROM BOSTON MY MOTHER IS FROM BOSTON WELL QUINCY ACTUALLY BUT DO YOU KNOW 127.0.1.1 THEY ARE A REALLY GOOD FRIEND OF MINE YOU SHOULD MEET I HEAR THEIR DAUGHTER IS A DOCTOR DONTYAKNOW AND YOU COULD…”

etc, etc?

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a-dubyesterday at 8:31 PM

the '90s version of finding the hiring manager or boss on linkedin to try and get a job was connecting to the company's public smtp server with telnet, using their name to probe different email address patterns with "rcpt to:" (those days the actual servers were often directly connected to the internet and would leak email address validity in how they would respond to rcpt to) and then sending them a nice email.

smtp grew up to be an antisocial curmudgeon. extended smtp starts with EHLO.

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