Ransomware Research
PayDOS Ransomware
PayDOS is a malicious ransomware strain that encrypts victim files and demands ransom payment for decryption. First observed in the wild on October 1, 2016, this ransomware has been actively targeting systems worldwide. Security researchers also track this malware under the aliases: Serpent.
Quick Facts
- Ransomware Family
- PayDOS
- First Seen
- October 1, 2016
- Known Aliases
- Serpent
How PayDOS Ransomware Works
Targeted Files
Renames files only
File Encryption Patterns
PayDOS modifies encrypted files using specific patterns to mark them as encrypted:
File extensions added after encryption:
..dnk..dpg..dif..dng -.dxe..dsi..dp3..dgg..dav..dov..dvi..dp4..dxt..drlRansom Note and Payment Demands
After encrypting files, PayDOS displays ransom notes demanding payment for file recovery:
Ransom message:
notes/note.txt
Note locations:
OnceOnCompletionREADME.txtRansom message:
notes/README.txt
Note locations:
RansomPayloadStartFolderTechnical Indicators
Associated Executable Files
The following executable files are associated with PayDOS ransomware:
Trojan.Ransom.PayDOS.exePayDOS_Ransomware_unlockcode_AES1014DW256SpikeSkype_SETUP.exeransomware (13).exe
Elastio Can Help You
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About This Analysis
This PayDOS 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 PayDOS.
Last updated: July 30, 2025