Re: Verifying E-Mail Addresses

[Jon Hart <jhart () spoofed org>]

On Tue, Oct 24, 2006 at 05:02:32PM -0400, Mister Dookie wrote:
> Hello list,
>
> Is there a way to verify that an e-mail address
> (e.g."johnsmith () company com") is valid and exists or does not exist
> (is a fake e-mail address) without actually sending a message to that
> address and awaiting the response?

At least with SMTP, there is the VRFY command.  However, this is
oftentimes turned off or configured to always return true.  Worth
a shot, however.

For example, with postfix's disable_vrfy_command turned off:

$  telnet spoofed.org 25           
Trying a.b.c.d..
Connected to spoofed.org.
Escape character is '^]'.
220 mail.spoofed.org ESMTP
vrfy root
252 2.0.0 root
vrfy warchild
252 2.0.0 warchild
vrfy blahblah
550 5.1.1 <blahblah>: Recipient address rejected: User unknown in local
    recipient table

-jon

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