Telnet 555 5.5.2 Syntax error. b42si7464989qgd.93 - gsmtp

3

I'm trying to do email spoofing in cmd in telnet but failed to do so.

I entered

C:\Documents and Settings\Owner>telnet alt3.gmail-smtp-in.l.google.com 25

Then it brought me here

220 mx.google.com ESMTP p59si7495147qga.25 - gsmtp

Typed this one

ehlo

Then it produced:

250-mx.google.com at your service, [122.54.217.133]
250-SIZE 35882577
250-8BITMIME
250-STARTTLS
250-ENHANCEDSTATUSCODES
250 CHUNKING

I continued typing this:

MAIL FROM:<cedrickapc@gmail.com>
502 5.5.1 Unrecognized command. s10si7413775qak.221 - gsmtp

Can someone please tell me why do I get error. Isn't it that Gmail is allowing outgoing mail relaying? And may I ask if I can use a disposable/temporary email provider such as dispostable.com for the recepient of this email?

Doha Kik

Posted 2014-04-01T11:34:02.857

Reputation: 31

try adding a carrige return and line feed followed by a semicolon at the end of the line (\r\n;). http://compquiz.blogspot.com/2011/03/smtp-trouble-shooting-error-500-551.html . 502 means unimplemented command, so obiviously the parser is not recognizing your command for one reason or other.

– Frank Thomas – 2014-04-01T11:44:57.710

Answers

2

It works fine for me, so I suspect there was an extra character in the MAIL FROM line confusing the parser.

$ telnet alt3.gmail-smtp-in.l.google.com 25
Trying 173.194.66.26...
Connected to alt3.gmail-smtp-in.l.google.com.
Escape character is '^]'.
220 mx.google.com ESMTP eu4si26638696wjd.51 - gsmtp
ehlo
250-mx.google.com at your service, [128.XXX.YYY.ZZZ]
250-SIZE 35882577
250-8BITMIME
250-STARTTLS
250-ENHANCEDSTATUSCODES
250 CHUNKING
MAIL FROM:<cedrickapc@gmail.com>
250 2.1.0 OK eu4si26638696wjd.51 - gsmtp
RSET
250 2.1.5 Flushed eu4si26638696wjd.51 - gsmtp
QUIT
221 2.0.0 closing connection eu4si26638696wjd.51 - gsmtp
Connection closed by foreign host.

Nick Russo

Posted 2014-04-01T11:34:02.857

Reputation: 979

Asked: 2014-04-01T11:34:02.857

Viewed: 11 480 times

Active: 2019-03-22T19:14:26.283