No es ningun agujero, pero ¿he podido enviar un email haciendo telnet al puerto 25?
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HELO -----------------.net
250 -----------------.net
MAIL FROM: <
lola@elhacker.net>
250 2.1.0 Ok
RCPT TO: <
lola@elhacker.net>
554 5.7.1 <
lola@elhacker.net>: Relay access denied
RCPT TO: <
lola@-----------------.net>
550 5.1.1 <
lola@-----------------.net>: Recipient address rejected: User unknown in virtual alias table
RCPT TO: <
root@-----------------.net>
250 2.1.5 Ok
DATA
354 End data with <CR><LF>.<CR><LF>
Prueba de envio
.
250 2.0.0 Ok: queued as 71F025B4094
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