UDP port 80 DDoS attack

Drew Weaver drew.weaver at thenap.com
Wed Feb 8 19:27:20 UTC 2012


Just a general note on the UDP 80 style DoS attacks.

I'm not entirely certain that UDP 80 attacks are always related to the gameserver bug that you're citing below.

We have seen in the wild php scripts that are hard coded to use UDP 80 to deliver DoS attacks towards their targets.

Basically it's just GET /script.php?ip.of.victim and instant UDP 80 flood, I've also seen perl versions of the same script.. most notably UDP.PL

What would be interesting is to see just how much UDP 80 traffic exists on the Internet at any given moment.

I don't know if Arbor's ATLAS really tracks traffic in that way but it would be interesting to get a semi-global view of just how many PPS/BPS are being wasted on these types of floods.

Maybe even as a research paper =)


-----Original Message-----
From: Fredrik Holmqvist / I2B [mailto:fredrik at i2b.se] 
Sent: Sunday, February 05, 2012 6:47 PM
To: nanog at nanog.org
Subject: Re: UDP port 80 DDoS attack


We had a customer that was attacked by the same "game server feature".
We received aprox 10 Gbit of traffic against the customer.

The attacker sends spoofed packets to the game server with the target IP as "source", the gameserver sends replies back via UDP to the target host. The attacker sends a couple of hundred packets per second and thus generating a 10 Mbit UDP flood.

There is fixes/workarounds for the game servers, just a matter of the admin taking care of it.
See: http://rankgamehosting.ru/index.php?showtopic=1320

The "attacking" IPs aren't spoofed, so just compile a list and send e-mails to each provider.

We had 1000+ IPs gathered and sent 100+ abuse e-mails, only received reply from less than 20%.
Sad that people care so little about mitigating DDoS/UDP/ICMP floods.

On Sun, 5 Feb 2012 18:36:13 -0500, Ray Gasnick III <rgasnick at milestechnologies.com> wrote:
> We just saw a huge flux of traffic occur this morning that spiked one 
> of our upstream ISPs gear and killed the layer 2 link on another 
> becuase of a DDoS attack on UDP port 80.
> Wireshark shows this appears to be from a compromised game server 
> (call of duty) with source IPs in a variety of different prefixes.
> Only solution thus far was to dump the victim IP address in our block 
> into the BGP Black hole community with one of our 2 providers and 
> completely stop advertising to the other.
> Anybody see this recently and have any tips on mitigation,  reply on 
> or off list.
> Thank You,
> Ray Gasnick III
> CISSP, Technology Specialist: Network Security & Infrastructure Miles 
> Technologies 
> www.milestechnologies.com<http://www.milestechnologies.com/>
> Phone: (856) 439-0999 x127
> Direct: (856) 793-3821
> How am I doing?  Email my manager at
> itmanager at milestechnologies.com<mailto:itmanager at milestechnologies.com
> >
> Computer Networking – IT Support – Business Software – Website Design 
> – Online Marketing & PR

Fredrik Holmqvist
I2B (Internet 2 Business)
070-740 5033

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