Ransomware Research

CryptXXX Ransomware

CryptXXX is a malicious ransomware strain that encrypts victim files and demands ransom payment for decryption. First observed in the wild on April 1, 2016, this ransomware has been actively targeting systems worldwide. Security researchers also track this malware under the aliases: CryptXXX 2.0.

Quick Facts

Ransomware Family
CryptXXX
First Seen
April 1, 2016
Known Aliases
CryptXXX 2.0

How CryptXXX Ransomware Works

File Encryption Patterns

CryptXXX modifies encrypted files using specific patterns to mark them as encrypted:

File extensions added after encryption:

..crypt..crypz..cryp1

Ransom Note and Payment Demands

After encrypting files, CryptXXX displays ransom notes demanding payment for file recovery:

file!README.HTML

Ransom message:

notes/!README.HTML

Note locations:

EveryFolder
filede_crypt_readme.txt

Ransom message:

notes/de_crypt_readme.txt

Note locations:

EveryFolder
filedecrypt-instructions.txt

Ransom message:

notes/decrypt-instructions.txt

Note locations:

EveryFolder
filedecrypt-instructions.html

Ransom message:

notes/decrypt-instructions.html

Note locations:

EveryFolder
filedecrypt-instructions.bmp

Ransom message:

notes/decrypt-instructions.bmp

Note locations:

EveryFolder
file/^@[A-F0-9]{12}\.html$/

Ransom message:

notes/@52CE675AD85E.html

Note locations:

EveryFolder
file/^@[A-F0-9]{12}\.txt$/

Ransom message:

notes/@52CE675AD85E.txt

Note locations:

EveryFolder
file/^![A-F0-9]{12}\.html$/

Ransom message:

notes/!4B3A1BD0EC11.html

Note locations:

EveryFolder
file/^![A-F0-9]{12}\.txt$/

Ransom message:

notes/!4B3A1BD0EC11.txt

Note locations:

EveryFolder

Technical Indicators

Associated Executable Files

The following executable files are associated with CryptXXX ransomware:

  • layouts.exe
  • adc0.tmp.dll
  • 3363.tmp.dll
  • rad30AF9.tmp.dll
  • rad24cd3.tmp.dll
  • rad5E0FA.tmp.dll

Elastio Can Help You

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About This Analysis

This CryptXXX ransomware analysis is part of Elastio's comprehensive ransomware detection database. Elastio provides advanced ransomware protection and recovery solutions, helping organizations defend against and recover from ransomware attacks like CryptXXX.

Last updated: September 30, 2025

What is CryptXXX Ransomware? | Elastio