Re: [Exim] Too many unrecognized commands

Página Principal
Apagar esta mensagem
Responder a esta mensagem
Autor: Phil Pennock
Data:  
Para: Kevin Reed, Exim Users Mailing List
Assunto: Re: [Exim] Too many unrecognized commands
On 2002-01-18 at 10:52 -0700, Kevin Reed wrote:
> I am assuming here, that this is protecting me from an attempt to
> subvert my MTA... If so... great!


Yes. "The HTML Form Protocol Attack",
<http://www.remote.org/jochen/sec/hfpa/hfpa.pdf>

> I just want to make sure that I am not rejecting a valid connection
> though if I look at the list that has the entries in it, bit really
> don't think that is so..
>
> Below are log entries that have the line:
>
>     dropped: too many unrecognized commands


For that to happen, the remote server must have already sent six
unrecognised commands. Exim supports EHLO, so that's one possible bad
command gone. Any extensions should be enabled by a keyword given in
the response to the EHLO command. There's no reason otherwise for there
to be unrecognised commands. VRFY and EXPN do not return "Unrecognized
command", even if not available.

Exim allows a few mistakes, because humans who test mail-servers do make
typos.
--
It seems to have reached the point where a user of a GNU/Linux distribution
will consider themselves "hot" if they can install the system on their own and
do the same for others, or a "guru" if they once used a command-line shell.