Ransomware Research

YYYYBJQOQDU Ransomware

YYYYBJQOQDU is a malicious ransomware strain that encrypts victim files and demands ransom payment for decryption. First observed in the wild on March 1, 2019, this ransomware has been actively targeting systems worldwide. Security researchers also track this malware under the aliases: Unnamed Chinese.

Quick facts

Ransomware Family
YYYYBJQOQDU
First Seen
March 1, 2019
Known Aliases
Unnamed Chinese

How YYYYBJQOQDU ransomware works

File encryption patterns

YYYYBJQOQDU modifies encrypted files using specific patterns to mark them as encrypted:

Extensions added after encryption
./\.[A-Z]{10,12}$/

Ransom note and payment demands

After encrypting files, YYYYBJQOQDU displays ransom notes demanding payment for file recovery:

fileYOUR FILES ARE ENCRYPTED.TXT
notes/YOUR FILES ARE ENCRYPTED.TXT

About this analysis

This YYYYBJQOQDU 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 YYYYBJQOQDU.

Last updated: December 30, 2025

Detection coverage

Elastio detects YYYYBJQOQDU inside your data and backups.

The Hunt Engine uses Deep File Inspection to identify YYYYBJQOQDU 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.

See How the Hunt Engine WorksRequest a Demo

Recent ransomware

Explore other threats in our database

Wxlongda2025VeilCrypt2025TitanLabooboo2025SolidBit2022SnapHackLocker2024PySystemUpdate2025PySimCrypt2025Monkey2025Lol2025HWID2025
View all ransomware →
What is YYYYBJQOQDU Ransomware? | Elastio