JSWorm Ransomware
JSWorm is a malicious ransomware strain that encrypts victim files and demands ransom payment for decryption. First observed in the wild on April 1, 2019, this ransomware has been actively targeting systems worldwide. Security researchers also track this malware under the aliases: JSWorm, JSWorm 2.0, JSWorm 3.0-3.1, JSWorm 4.0.2-4.0.3.
Quick facts
How JSWorm ransomware works
File encryption patterns
JSWorm modifies encrypted files using specific patterns to mark them as encrypted:
Ransom note and payment demands
After encrypting files, JSWorm displays ransom notes demanding payment for file recovery:
notes/JSWORM-DECRYPT.html
notes/UNNAMED-DECRYPT.txt
notes/JSWORM-DECRYPT.txt
notes/JSWRM-DECRYPT.hta
notes/TRUMP-DECRYPT.txt
notes/JBUIIGF-DECRYPT.txt
Technical indicators
Associated executable files
The following executable files are associated with JSWorm ransomware:
- JSWorm.exe
- build.exe
- MANWARD6
- MANWARD6.exe
- 5527.exe
- jsworm.exe
- svchost.exe
About this analysis
This JSWorm 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 JSWorm.
Last updated: December 30, 2025
Elastio detects JSWorm inside your data and backups.
The Hunt Engine uses Deep File Inspection to identify JSWorm 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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