Avast Decryption Tool for CryptoMix can unlock the CryptoMix ransomware (also known as CryptFile2 or Zeta) and later CryptoShield. All the Avast Decryption Tools are available in one zip here.

Both variants encrypt files by using AES256 encryption with a unique encryption key downloaded from a remote server. However, if the server is not available or if the user is not connected to the internet, the ransomware will encrypt files with a fixed key ("offline key").

Important: The provided decryption tool only supports files encrypted using an "offline key." In cases where the offline key was not used to encrypt files, our tool will be unable to restore the files, and no file modification will be done.

Most of the messages look similar, as seen in the screenshots below.

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