THRsx Ransomware

A recent case involved a small business in Europe whose critical documents—spreadsheets, contracts, and images—were encrypted overnight. The attackers replaced all files with the extension “.THRsx” and dropped a ransom note demanding payment in Bitcoin. Victims faced a stark reality: pay up or risk losing access permanently.

Threat Overview

THRsx falls squarely in the ransomware category: malicious software that encrypts files, making them inaccessible without a decryption key. Its goal? Coerce victims into paying a ransom. If stolen data is exfiltrated before encryption, it’s often a “double-extortion” tactic—encrypt files and threaten to leak the stolen data.

Key Details

In‑Depth Analysis

Infection Vector

THRsx is typically delivered via phishing campaigns—emails masquerading as invoices or support tickets containing malicious links or attachments. It also spreads through malvertising or exploit kits on compromised websites.

Behavioral Profile

1. Initial execution: The malware runs quietly in the background after launch.
2. Data exfiltration: If programmed, it steals sensitive documents before encrypting.
3. File encryption: It targets key file types—Word, Excel, PDFs, images—renaming them with .THRsx.
4. Ransom note: Drops a text or HTML note (such as !!!READMETHRsx.txt) on the desktop with payment instructions.
5. Persistence: Changes registry keys or schedules tasks to ensure it runs after reboot.

Risk Assessment

THRsx presents a high risk—it locks organizations and individuals out of critical data, with potential double extortion. Real-world ransomware events like the 2019 Lake City, FL attack highlight how downtime can cost hundreds of thousands. For example, Lake City paid nearly $460,000 to restore services and operations.

Artifact Text

Sample ransom note (“!!!READMETHRsx.txt”):

Your files have been encrypted with THRsx Crypto.
To recover them, send 0.5 BTC to:
1A2b3C4d5E6f7G8h9I0jK1L2mNoP3Q4rS
Then email your transaction ID and ID: XXXXX to example@tremail.com

Manual Ransomware Removal Guide

Warning: Manual removal is complex and risky. If not done correctly, it can lead to data loss or incomplete removal of ransomware. Only follow this method if you are an advanced user. If unsure, proceed with Method 2 (SpyHunter Removal Guide).

Step 1: Disconnect from the Internet

1. Unplug your Ethernet cable or disconnect Wi-Fi immediately to prevent further communication with the ransomware’s command and control (C2) servers.

Step 2: Boot into Safe Mode

For Windows Users:

1. For Windows 10, 11:
   • Press Windows + R, type msconfig, and hit Enter.
   • Go to the Boot tab.
   • Check Safe boot and select Network.
   • Click Apply and OK, then restart your PC.
2. For Windows 7, 8:
   • Restart your PC and press F8 repeatedly before Windows loads.
   • Select Safe Mode with Networking and press Enter.

For Mac Users:

1. Restart your Mac and immediately press and hold the Shift key.
2. Release the key once you see the Apple logo.
3. Your Mac will start in Safe Mode.

Step 3: Locate and Terminate Malicious Processes

For Windows Users:

1. Press Ctrl + Shift + Esc to open Task Manager.
2. Look for suspicious processes (e.g., unknown names, high CPU usage, or random letters).
3. Right-click on the process and select End Task.

For Mac Users:

1. Open Activity Monitor (Finder > Applications > Utilities > Activity Monitor).
2. Look for unusual processes.
3. Select the process and click Force Quit.

Step 4: Delete Malicious Files

For Windows Users:

1. Press Windows + R, type %temp%, and hit Enter.
2. Delete all files in the Temp folder.
3. Navigate to:
   • C:\Users\[Your Username]\AppData\Roaming
   • C:\Users\[Your Username]\AppData\Local
   • C:\Windows\System32
4. Look for suspicious files related to the ransomware (random file names, recently modified) and delete them.

For Mac Users:

1. Open Finder and go to Go > Go to Folder.
2. Type ~/Library/Application Support and delete suspicious folders.
3. Navigate to ~/Library/LaunchAgents and remove unknown .plist files.

Step 5: Remove Ransomware from Registry or System Settings

For Windows Users:

Warning: Incorrect changes in the Registry Editor can damage your system. Proceed with caution.

1. Press Windows + R, type regedit, and hit Enter.
2. Navigate to:
   • HKEY_CURRENT_USER\Software
   • HKEY_LOCAL_MACHINE\Software
3. Look for unfamiliar folders with random characters or ransomware-related names.
4. Right-click and select Delete.

For Mac Users:

1. Go to System Preferences > Users & Groups.
2. Click on Login Items and remove any suspicious startup items.
3. Navigate to ~/Library/Preferences and remove malicious .plist files.

Step 6: Restore System Using System Restore (Windows) or Time Machine (Mac)

For Windows Users:

1. Press Windows + R, type rstrui, and hit Enter.
2. Click Next, choose a restore point before the infection, and follow the prompts to restore your system.

For Mac Users:

1. Restart your Mac and hold Command + R to enter macOS Utilities.
2. Select Restore from Time Machine Backup.
3. Choose a backup prior to the ransomware infection and restore your system.

Step 7: Use a Decryption Tool (If Available)

• Visit No More Ransom (www.nomoreransom.org) and check if a decryption tool is available for your ransomware variant.

Step 8: Recover Files Using Backup

• If you have backups on an external drive or cloud storage, restore your files.

Automatic Ransomware Removal Using SpyHunter

If manual removal seems too risky or complicated, using a reliable anti-malware tool like SpyHunter is the best alternative.

Step 1: Download SpyHunter

Download SpyHunter from the official link: Download SpyHunter

Or follow the official installation instructions here:
SpyHunter Download Instructions

Step 2: Install SpyHunter

1. Open the downloaded file (SpyHunter-Installer.exe).
2. Follow the on-screen prompts to install the program.
3. Once installed, launch SpyHunter.

Step 3: Perform a Full System Scan

1. Click on Start Scan Now.
2. SpyHunter will scan for ransomware and other malware.
3. Wait for the scan to complete.

Step 4: Remove Detected Threats

1. After the scan, SpyHunter will list all detected threats.
2. Click Fix Threats to remove the ransomware.

Step 5: Use SpyHunter’s Malware HelpDesk (If Needed)

If you are dealing with a stubborn ransomware variant, SpyHunter’s Malware HelpDesk provides custom fixes to remove advanced threats.

Step 6: Restore Your Files

If your files are encrypted:

• Try No More Ransom (www.nomoreransom.org) for decryption tools.
• Restore from cloud storage or external backups.

Preventing Future Ransomware Attacks

• Keep backups on an external hard drive or cloud storage.
• Use SpyHunter to detect threats before they infect your system.
• Enable Windows Defender or a trusted antivirus program.
• Avoid suspicious emails, attachments, and links.
• Update Windows, macOS & software regularly.

Conclusion

THRsx is an aggressive ransomware variant that encrypts crucial files and often threatens data leakage. Prompt detection, isolation, and removal—followed by data recovery from backups—are essential. Avoid paying ransoms: doing so only funds criminal operations and does not guarantee data return.