Mespinoza Ransomware
Mespinoza is a malicious ransomware strain that encrypts victim files and demands ransom payment for decryption. First observed in the wild on November 1, 2019, this ransomware has been actively targeting systems worldwide. Security researchers also track this malware under the aliases: Mespinoza, Pysa, Mespinoza Doxware.
Quick facts
How Mespinoza ransomware works
File encryption patterns
Mespinoza modifies encrypted files using specific patterns to mark them as encrypted:
Ransom note and payment demands
After encrypting files, Mespinoza displays ransom notes demanding payment for file recovery:
notes/Readme.README
Technical indicators
Associated executable files
The following executable files are associated with Mespinoza ransomware:
- 51.exe
- 628637.exe
- 1.exe
- Mespinoza.exe
About this analysis
This Mespinoza 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 Mespinoza.
Last updated: December 30, 2025
Elastio detects Mespinoza inside your data and backups.
The Hunt Engine uses Deep File Inspection to identify Mespinoza 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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