Re: suspicious firewall rules in WinXP firewall

[kent crispin <kent () songbird com>]

It appears that perhaps the resolver software/configuration has been altered
so that dns queries will go to alternate root servers.  I would be very
curious to know what addresses dns queries are actually trying to hit... 

On Fri, Jun 30, 2006 at 08:32:09PM -0000, belka () att net wrote:
> While setting a port for Symantec to query XP Pro workstations for virus
updates, I noticed two machines that had firewall rules (exceptions in WinXP
firewall parlance) that were in unreadable charcaters, such as an asian font
set that couldn't be displayed.  The rule name was in blocks or in other
unreadable characters.  The user of these two workstations is notorious for
downloading asian TV shows over bit torrent, and visiting anime and other
asian sites. 
> I deleted the two firewall rules (DOH! I should have just disabled them)
and now IE and Mozilla browsers do not work at all.  I can ping out of these
two machines, and as long as I use an IP address, these machines can ping
anywhere in the Internet.  However, if any call to DNS is requires, either
with a browser or ICMP, it fails. 
> Has anyone had a similar experience or seen this kind of behavior.  My fear
is that one of the "special Korean download programs" that this user admits
installing has altered the browser or -- even worse - the XP TCP/IP stack
with hooks into a trojan or spyware product.  I tried disabling the firewall
to allow all traffic in and out, but to no effect.  No DNS functionality.  My
packet traces are inconclusive and my IDS is not alerting on anything in or
out of these two work stations. 
> Any ideas? At this point I know I am going to have to reload, but from a
forensic stand point, I am curious if any one else has seen this kind of
beavior before. 
> Thanks.

-- 
Kent Crispin 
kent () icann org    p: +1 310 823 9358  f: +1 310 823 8649
kent () songbird com SIP: 81202 () fwd pulver com


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