Unit09 Ransomware
Unit09 is a malicious ransomware strain that encrypts victim files and demands ransom payment for decryption. First observed in the wild on January 1, 2019, this ransomware has been actively targeting systems worldwide. Security researchers also track this malware under the aliases: MewWare.
Quick facts
How Unit09 ransomware works
File encryption patterns
Unit09 modifies encrypted files using specific patterns to mark them as encrypted:
Ransom note and payment demands
After encrypting files, Unit09 displays ransom notes demanding payment for file recovery:
notes/$!READ ME.txt
About this analysis
This Unit09 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 Unit09.
Last updated: December 30, 2025
Elastio detects Unit09 inside your data and backups.
The Hunt Engine uses Deep File Inspection to identify Unit09 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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