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CryptoLocker Removal

I have a network that has just been hit with Crypto locker or a variant of Crypto. It seens to have infected a single workstation but there are encrypted files on some of the Server shares as well. As a precaution we have shut down the server and the infected work station and most of the rest of the network as well.

Questions :

1 - What is the best software that can remove the CryptoLocker software please?
2 - Do the encrypted files pose any threat to the system - can the infection spread from encrypted files on other machines that host shares that appear on the infected machine?
3 - Can the removal software be run on the infected machine or is it best to put the disc in a good machine and run the removal from there?
4 - Is there really any way to restore encrypted files? I fear I know the answer to this one already...

Thank you

rindi

No need to shut the server down, just the workstation. The encrypted files don't pose any threat. Just delete those and restore them from your backups. There is no way to decrypt them without the key, and of course it is needless to say that you mustn't pay up the ransom to maybe get that key.

Get in touch with your law enforcement authorities first, maybe they want to look at the infected PC. That might help them to get tags on the crooks, or help for future instructions to avoid getting the virus.

Once the authorities tell you it is OK, just re-image the PC. That is the fastest and safest way to get rid of the bugs.

As precautions for the future, make sure the users never log on to any PC using an account with admin rights. Only ever use standard accounts. educate the users on how to use the internet and email. Only visit sites you trust, open attachments from people you trust and from whom you are expecting attachments. Make sure the PC's are fully patched and the AV tool updated. Basically all the common sense stuff.

Also make sure your backups are OK, and that you rotate your backup media and have several versions.

broadsoft

ASKER

Thanks for that advice - can you advise please how do I know for sure which computer is the infected one? The desktop I refer to is the only one with encrypted files on it but I really need to be sure that the crypto exe has not propagated to the server and other work stations. Is there a good malware detection / removal tool that can be trusted to detect and remove this?

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rindi

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btan

in case you are interested for Ransomware preventive measures, I do suggest a more holistic measures such as application whitelisting, so do check out some EE articles
https://www.experts-exchange.com/articles/18086/Ransomware-Prevention-is-the-only-solution.html
https://www.experts-exchange.com/articles/20879/Ransomware-is-rampant-don't-be-caught-out.html
https://www.experts-exchange.com/articles/21199/Ransomware-Beware.html

Dave Howe

This might be of interest/applicable: http://thehackernews.com/2015/10/ransomware-decryption-tool.html

broadsoft

ASKER

Thank you Dave for that - indeed I am very interested! Very much appreciated.