Re: Source port 0 and from a 0 network to boot?
kurt <[email protected]>
| Newsgroups | gmane.comp.security.incidents |
|---|---|
| Message-ID | <[email protected]> |
0 may be a legit first octet but more realistically this PCs address was actually 10.153.189.110. So the source addresses we knew where spoofed. I'm wondering if this looks like any known bot/trojan/whatever? this was a definate attempt to DoS the destination, too bad it DoS'd a local network. it may have been the writer of this bot/trojan/whatever had assumed the exploited PC would be closer to a perimeter (ie: home broadband) and not deep within a network? the box was taken off-line and by now i'm guessing it's been rebuilt <bummer> forensics? probably not...... oh well. On 11 Jun 2005 19:08:31 -0000, [email protected] <[email protected]> wrote: > The destination website advises they're experiencing 'server problems'. I would have to guess it's a trojan or botnet DDoS/SYN flood attack. > > As far as the port 0 traffic, a quote from an old Neohapisis archive "Using TCP port 0 is a common tactic to avoid some badly written packet > filters.... Some net admins fail to realize that there is a port 0, > thinking that the lowest port number is 1, and thus don't account for it > when writing firewall rules. > > An attacker gains the advantage of possibly bypassing firewall rules, or > badly written intrusion sensors. > > It should also be noted that very, very, old versions of DNS were done on > port 0, but that wasn't done using TCP." > > Probably just disguising the attacking host (though not very well) to slow down the filtering/blocking of attackers. >