NullByte Ransomware
NullByte is a malicious ransomware strain that encrypts victim files and demands ransom payment for decryption. First observed in the wild on August 1, 2016, this ransomware has been actively targeting systems worldwide. Security researchers also track this malware under the aliases: Necrobot.
Quick facts
How NullByte ransomware works
File encryption patterns
NullByte modifies encrypted files using specific patterns to mark them as encrypted:
Ransom note and payment demands
After encrypting files, NullByte displays ransom notes demanding payment for file recovery:
notes/note.txt
notes/bg.jpg
About this analysis
This NullByte 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 NullByte.
Last updated: December 30, 2025
Elastio detects NullByte inside your data and backups.
The Hunt Engine uses Deep File Inspection to identify NullByte 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.
Recent ransomware
Explore other threats in our database