Friday, September 04, 2009

Extreme Asymmetry in Network Attack and Defense

As usual, Gunter Ollmann posted a great story on the Damballa blog titled Want to rent an 80-120k DDoS Botnet? He writes:

[T]his particular operator is offering a botnet of between 80k and 120k hosts capable of launching DDoS attacks of 10-100Gbps – which is more than enough to take out practically any popular site on the Internet. The price for this service? $200 per 24 hours – oh, and there’s a 3 minute try-before-you-buy.

Someone please tell me how much it costs to provision equipment and services sufficient to sustain network operations during a 10-100 Gbps DDoS attack. I bet it is much more than $200 per day. This extreme level of asymmetry demonstrates another reason why intruders have the upper hand in network attack and defense.

Situations like this remind me that an insurance model might work. Insurance works when many contribute but few suffer simultaneous disasters. Perhaps organizations could buy insurance policies to cover losses due to DDoS, rather than provision for the disaster? Or do organizations already do that? I know some work with companies like Prolexic specifically to mitigate DDoS, but how about with insurers?

6 comments:

Andre Gironda said...

BGP and DNS are relatively free. Announce dark IP space and move your servers to it when under attack. Adversaries change IPs? Change servers to another new prefix. Repeat.

Adversaries typically use DDoS in <5 minute increments (that 3 minute try-before-buy is crazy, btw!). They probably give up somewhere between 2-12 tries.

How much do 12 non-contiguous /24 PA prefixes cost? A /20 of PI space (contiguous) costs less than $3k one-time for an end-user. A /20 will last most organizations 8 years or longer. That's about $30/month.

Richard Bejtlich said...

The effort required to perform that work is going to exceed $200 per day. Even with outsourced IT you're not going to defend yourself for less than $16.67 per hour. :)

Andre Gironda said...

You're trying to tell me that your average managed service IT/Ops worker makes $17/hour, but you're not remembering that your average online criminal is probably making at least five times that per hour. There's your symmetry right there!

No wonder criminals are moving to DDoSaaS models. However, to your point, one can't measure the cost of fear.

Richard Bejtlich said...

Hi Andre, I meant that I doubt you can staff network operations for less than $16.67 per hour (or $200 per 24 hours). So, the increased cost on the defense side for staffing alone is a problem for the victims.

Richard Bejtlich said...

It would be nice to know the botmaster's expenses. How much to buy a kit, acquire lower level C&C servers, bulletproof hosting for higher level C&C servers, money spent on phishing campaigns, "advertising," client development, etc.

On the victim side, we should try to assess the cost of the DDoS.

Dave Funk said...

I personnaly like the insurance concept. Individual businesses typically do not go after these guys because it isn't worth the effort. Law enforcement doesn't go after them because they don't have the resources. Insurance investigators take care of both these problems. Problem is that the inspection of a workspace for a fire insurance inspection is pretty straight-forward. For Information Security, far less so. Come to think of it, insurance could do something for that problem also!