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Cryptolocker - why not block the C&C?

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#1 medconn


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Posted 17 November 2013 - 10:57 AM

I know that CryptoLocker uses "randomly generated" DNS names to talk to it's C&C machine, but surely it shouldn't be too difficult to reverse engineer the code, copy that list and to block them at the DNS level. I realise that IP level blocks wouldn't work, as the developers would simply "poison" the DNS with otherwise important IP addresses, making the collateral damage from that approach too much, but the DNS level looks feasible - what am I missing? 

Edited by medconn, 17 November 2013 - 10:58 AM.

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#2 noknojon


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Posted 17 November 2013 - 03:36 PM

Hi medconn -

The Encryption is started after a "minor infection" is inserted on the system.

Once it is infected the Encryption has already taken place, and their server that infected that computer, may not be the one to supply the Decryption codes back to you.


I have reverse traced 2 linked IP addresses given so far, and these hopped over many links back as far as I could trace, them till they were lost somewhere out the back of Russia -

It went Russia > Scandanavia (may be Holland) > France > Britian > USA East coast > USA mid states > USA West coast - From there it may have hopped again, but I lost both ends of the trace after that.

This is just one reason why they are almost unable to be tracked from a single point .....


A long description, but these crooks have done their homework prior to the release of any Encryption.


The infection carrier is "nothing", it is the Encryption phase that causes the problem.


Thank You -

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