KK Ransomware
KK 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: Estonian.
Quick facts
Ransom note and payment demands
After encrypting files, KK displays ransom notes demanding payment for file recovery:
notes/KK_ IN YOUR DOCUMENTS..txt
About this analysis
This KK 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 KK.
Last updated: December 30, 2025
Elastio detects KK inside your data and backups.
The Hunt Engine uses Deep File Inspection to identify KK 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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