KCW Ransomware
KCW is a malicious ransomware strain that encrypts victim files and demands ransom payment for decryption. First observed in the wild on April 1, 2018, this ransomware has been actively targeting systems worldwide.
Quick facts
How KCW ransomware works
File encryption patterns
KCW modifies encrypted files using specific patterns to mark them as encrypted:
Ransom note and payment demands
After encrypting files, KCW displays ransom notes demanding payment for file recovery:
notes/kcwdecrypt.php.txt
About this analysis
This KCW ransomware analysis is part of Elastio's comprehensive ransomware detection database. Elastio provides advanced ransomware protection and recovery, helping organizations defend against and recover from ransomware attacks like KCW.
Last updated: December 30, 2025
Elastio detects KCW inside your data and backups.
The Hunt Engine uses Deep File Inspection to identify KCW across live data, replicated data, and backups. If this family is in your environment, Elastio finds it before encryption completes. Run a scan against your recovery points to confirm.
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