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keyword search for cryptolocker-like encrypted files

Posted on 2015-01-05
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Last Modified: 2015-01-22
Recently we were hit by cryptolocker and were able to recover all our files from backups.  Now I periodically search our network file shares for keyword: decrypt

I do this to make sure there are no more cryptolocker-encrypted files on the network, since when cryptolocker encrypts files, it creates a decryptinstructions.txt (or something like that) file in every folder it infects.

But now I want to broaden my search and look for some other possible programs of the same type (or the results of those programs).

What else can I search for besides the keyword "decrypt" to look for tell-tale signs that a folder has been hit by other-than-cryptolocker programs that do the same type of thing (encrypt files for ransom).

Is there a website that lists variants and specifically lists what to look for in a file system.

And yes, I do have AV software... we had it when we originally got hit with cryptolocker.

Anyway, thanks for any help anyone can come up with on this subject.
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Question by:gateguard
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btan earned 500 total points
ID: 40533048
This is one good source fro Cryptolocker and its history of events in its CryptoLocker Timeline as well as Guide Updates. http://www.bleepingcomputer.com/virus-removal/cryptolocker-ransomware-information

It may highlight variant appearance but I rather use its search entry in the site to sieve out all such the variant and family of same ransomware genre. Below are the some key variants from the search.  
Also in specific for scavenging possible infection machine etc, it is good to see in each surfaced sample in its stated "Associated <Ransomware> Files" section, which is normally way below in each article. You can find those files or trails deposited during their infection.

I extracted some and left out some random folder and files created since it is not going to be useful for hunt. The keyword list may include the filename or even wildcard it if your script support that...
http://www.bleepingcomputer.com/virus-removal/cryptowall-ransomware-information
%UserProfile%\Desktop\DECRYPT_INSTRUCTION.HTML
%UserProfile%\Desktop\DECRYPT_INSTRUCTION.TXT
%UserProfile%\Desktop\DECRYPT_INSTRUCTION.URL
%UserProfile%\Desktop\INSTALL_TOR.URL
http://www.bleepingcomputer.com/virus-removal/coinvault-ransomware-information
%AppData%\Microsoft\Windows\coinvault.exe
%AppData%\Microsoft\Windows\edone
%AppData%\Microsoft\Windows\filelist.txt
%Temp%\CoinVaultFileList.txt
%Temp%\wallpaper.jpg
http://www.bleepingcomputer.com/virus-removal/cryptodefense-ransomware-information
%UserProfile%\Desktop\HOW_DECRYPT.HTML
%UserProfile%\Desktop\HOW_DECRYPT.TXT
%UserProfile%\Desktop\HOW_DECRYPT.URL
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by:btan
ID: 40564313
Also I added in for  CTB Locker , another ransomware

http://www.bleepingcomputer.com/virus-removal/ctb-locker-ransomware-information#files

%Temp%\<random>.exe
%MyDocuments%\AllFilesAreLocked <user_id>.bmp
%MyDocuments%\DecryptAllFiles <user_id>.txt
%MyDocuments%\<random>.html
%WinDir%\Tasks\<random>.job

And can have random file extension is .ztswgmc or .rlspiam
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