Author: Ian Southam Date: To: Marc Peiser CC: exim-users Subject: Re: [Exim] vulnerabilities
On Fri, Jan 28, 2000 at 05:15:43PM +0000 Marc Peiser wrote :
> "SMTP daemons on your machine supports features (such as EHLO, RCPT, VRFY
> and EXPN) which my enable hackers to gain information which could be used
> to exploit other vulnerabilities."
>
> Are they been stupid or is there some precautions I can take?
Hello,
To save you any more embarrasment, your consultants are talking rubbish.
VRFY and EXPN can give out information about your network to third parties
which you may not want to make available. For this reason I think both (but
certainly VRFY) are disabled by default in Exim.
EHLO and RCPT however, if disabled would almost certainly reult in your site
being unable to receive mail at all. this would certainly be secure but maybe
just a tad over zealous.