BTCWare, also known as CrptXXX and CryptoByte, targets Windows OS and is distributed manually via Remote Desktop Protocol (RDP) compromise.

Extensions appended to encrypted file names:
.btcware, .cryptobyte, .cryptowin, .[].theva, .onyon

Ransom note file names:
#_HOW_TO_FIX_!.hta, READ ME.txt, #_HOW_TO_FIX.inf, .!#_DECRYPT_#!.inf

Email addresses associated with BTCWare:,,,, decrypt

Telegram usernames associated with BTCWare:

Malware executables associated with BTCWare:
mfskskfkls.exe, <ransom>.exe, czsdxxs.exe

Ransom demand:
0.5 Bitcoin

UPDATE 5/16/2017: BTCWare master key was released and the free decryption tool linked below has been updated to include most versions of this variant.

  • The Bleeping Computer forums have more information about BTCWare here.
  • Bleeping Computer provides a free decryption tool for BTCWare here.

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