BlockFile12 Ransomware
BlockFile12 is a malicious ransomware strain that encrypts victim files and demands ransom payment for decryption. First observed in the wild on May 1, 2017, this ransomware has been actively targeting systems worldwide.
Quick facts
How BlockFile12 ransomware works
File encryption patterns
BlockFile12 modifies encrypted files using specific patterns to mark them as encrypted:
Ransom note and payment demands
After encrypting files, BlockFile12 displays ransom notes demanding payment for file recovery:
About this analysis
This BlockFile12 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 BlockFile12.
Last updated: December 30, 2025
Elastio detects BlockFile12 inside your data and backups.
The Hunt Engine uses Deep File Inspection to identify BlockFile12 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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