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<font size="-1"><font face="Verdana">Thanks for the detailed reply
:)<br>
<br>
Within 8hours got 7million inbound spoofed packets.<br>
<br>
Those were 7million abusive requests ... all apparently coming
from a single IP source (I'm seeing that same source querying
hundreds of other gameservers in different dacenters)<br>
That's something like a constant flow of 200packets/seconds from
a single source... looks like they are trying to exploit some of
our gameservers as reflectors...<br>
The source ip appear offline and unreacheable ... dunno which
services it is serving... but seeing the rates I'm pretty sure
that the source it's really that ip...<br>
<br>
In this moment these are the stats on a connection:<br>
rx: 12.28 Mbit/s 15878 p/s tx: 11.95 Mbit/s
9805 p/s<br>
<br>
Nearly 5k out of those 15k incoming packets are spoofed.<br>
5000packets / second filtered out...<br>
<br>
the 12p/s figure you were referring to is very rare here.. or at
least it's covered by these big attacks...<br>
<br>
Unless you were talking about 12packets to each single
gameserver instance... in such a case that would be possible...
we have a lot of gameservers running and the stats I was
referring above were overall stats...<br>
</font></font><br>
Il 18/01/2011 21:59, John ha scritto:
<blockquote cite="mid:4D35FF31.1000300@nuclearfallout.net"
type="cite">
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On 1/18/2011 5:51 AM, Marco Padovan wrote:
<blockquote cite="mid:4D359AD2.5070500@gmail.com" type="cite"><font
size="-1"><font face="Verdana">We are getting hit HARD (.eu)<br>
<br>
I dunno what's the tool you are referring to... could you
please mail me some references privately so I can analyze
it?<br>
</font></font></blockquote>
<br>
I was guessing that there is a new tool out there that is making
this easy. I don't know for certain if this is actually the case,
but it seems likely, considering the attack frequency and
large-ranging target set.<br>
<br>
<blockquote cite="mid:4D359AD2.5070500@gmail.com" type="cite"><font
size="-1"><font face="Verdana"> Basically we are currently
dealing on a daily basis with </font></font><font size="-1"><font
face="Verdana">this kind of attacks</font></font><font
size="-1"><font face="Verdana"> since december ...<br>
<br>
We find ourself handling 10k incoming spoofed packets per
second during certain times of the day...<br>
<br>
What are you referring to small flow? 1k/sec?
100packets/sec?<br>
</font></font></blockquote>
<br>
On the reflector side, maybe a dozen packets per second, at most.
So few that we don't even notice a problem with the server.<br>
<br>
<blockquote cite="mid:4D359AD2.5070500@gmail.com" type="cite"><font
size="-1"><font face="Verdana"> Which kind of rate limiting
figures did you all applied?<br>
We are trying to defend our self with very very strict
network filters... but that's damaging also our services
that certain times appear unreachable (even if they are not)<br>
</font></font></blockquote>
<br>
I haven't seen many of the reflections; I've mostly seen these
attacks as a target. In those cases, filtering by strings that are
specific to query responses seems to work best (when the attack is
small enough to be filtered on our end), but other techniques have
also been necessary at times.<br>
<br>
<blockquote cite="mid:4D359AD2.5070500@gmail.com" type="cite"><font
size="-1"><font face="Verdana"> In our case it looks like it's
not just against other gameservers... but also against
random hosts...<br>
Source packets sometimes are from port 80 udp and, if not
blocked, replies would do an udp flood to the poor host if
enough gameservers were involved... (even if no udp service
was running on port 80) :(<br>
</font></font></blockquote>
<br>
Against TCP-based services on a unique IP, an ACL on the upstream
side to filter all UDP should take care of this for them, at
least.<br>
<br>
The attacks are most effective against other game servers that
respond on UDP. Source servers, for instance, seem to be
particularly vulnerable.<br>
<br>
<blockquote cite="mid:4D359AD2.5070500@gmail.com" type="cite"><font
size="-1"><font face="Verdana"> The worst thing is that the
damage to us as "reflectors" is very low as we are used to
handle a shitload of packets so it's difficult to say if
there's an attack going on or not :/<br>
</font></font></blockquote>
<br>
Nod, I agree. From the reflector's perspective, the attacks are
almost impossible to detect.<br>
<br>
<blockquote cite="mid:4D359AD2.5070500@gmail.com" type="cite"><font
size="-1"><font face="Verdana"> Additionally, as I'm providing
services to different GSP brands in different countries, I
found out that attacks are basically spread on ALL the
servers... using all the servers available on the master
list as reflectors and targeting only a little number of
victims... they are not exploiting just a single GSP /
gameserver :|<br>
</font></font></blockquote>
<br>
That's what I have seen as well. I counted the IPs involved in one
attack early this month and found that there were over 3500 used
in a 30-second span of time. <br>
<br>
Black Ops servers were frequently used for this in December but I
believe that GS coordinated with Treyarch to get a rate limiting
feature put in place with that game.<br>
<br>
-John<br>
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