Ransomware Research
Jamper Ransomware
Jamper is a malicious ransomware strain that encrypts victim files and demands ransom payment for decryption. First observed in the wild on March 1, 2019, this ransomware has been actively targeting systems worldwide. Security researchers also track this malware under the aliases: Jumper.
Quick Facts
- Ransomware Family
- Jamper
- First Seen
- March 1, 2019
- Known Aliases
- Jumper
How Jamper Ransomware Works
Targeted Files
Encrypts first 64kb
File Encryption Patterns
Jamper modifies encrypted files using specific patterns to mark them as encrypted:
File extensions added after encryption:
..jamper..SONICRansom Note and Payment Demands
After encrypting files, Jamper displays ransom notes demanding payment for file recovery:
---README---.TXTRansom message:
notes/---README---.TXT
Note locations:
EveryFolderTechnical Indicators
Associated Executable Files
The following executable files are associated with Jamper ransomware:
DEFENDER.EXEdefender.exedefender.exe.VIRUS
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About This Analysis
This Jamper 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 Jamper.
Last updated: July 30, 2025