How to catch a cracker in the US?

Mark Seiden mis at
Wed Mar 12 18:38:39 UTC 2014

On Mar 12, 2014, at 9:56 AM, William Herrin <bill at> wrote:

> On Tue, Mar 11, 2014 at 3:00 AM, Markus <universe at> wrote:
>> I'm an ISP in Germany and a cracker (not a hacker :) ) has targeted a
>> customers of mine in the last days. The cracker was successful and caused
>> financial damage / was successful with data theft. I set a trap and finally
>> caught his real IP address - a Comcast user in the US (100% not a proxy or
>> bot). What would be the next steps to pursuit him? If I contact local
>> authorities here in Germany I'm afraid months will pass by and Comcast will
>> have possible already deleted their logs by then (?). Any advice?
> Hi Markus,
> A couple of suggestions:
> 1. Ask Comcast to preserve the records associated with the IP
> addresses and timeframe in which the problem occurred. They can't give
> them to you absent a valid US subpoena but they can save them from
> automatic deletion while you work on that.
> 2. Be specific about the problem. Be liberal with the shared details!
> Comcast can be your partner in this endeavor. If you treat them as
> your enemy by being cagey, they may behave as your enemy by doing the
> minimum required by law. Which turns out to be not much.
> 3. Once you have done these things, then go to the police. Share
> information about your specific contact with Comcast with the police
> and share your specific police contact with Comcast. This will start
> them talking, which is half the battle in getting the police to
> investigate a computer crime. Who knows, U.S. authorities may already
> be investigating the same user which would make your job so much
> easier.

how long ago did this happen?
they preserve subscriber information forever, and dhcp logs for 
quite a long time.

the police = your local federal police.

there is an mlat between .de and .us which means the us police has to
cooperate and pursue german cases and vice versa.  yes, it takes longer.  

there is also a hotline system where the .de police can request 
records preservation by US entities with the promise that an 
mlat request is forthcoming.

> Regards,
> Bill Herrin
> -- 
> William D. Herrin ................ herrin at  bill at
> 3005 Crane Dr. ...................... Web: <>
> Falls Church, VA 22042-3004

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