Monkey Ransomware Decryptor
After deep malware analysis and variant tracking, our research team designed a specialized decryptor specifically for the Monkey ransomware family — which encrypts data and adds the .monkey extension. The tool is optimized for reliability in Windows and server environments and employs a layered strategy: file-sample assessment, Chaos-family pattern matching, and blockchain-verified logging to ensure integrity during recovery. Its main objective is to decrypt files without altering forensic evidence or risking further damage.
How It Works
Each case begins with an analysis of a limited number of encrypted files in an isolated security sandbox. This helps identify the encryption model and specific variant family.
Next, the decryptor extracts and correlates victim-specific identifiers from the ransom note (How_to_recover_your_files.txt) to align with the unique encryption session.
When a verified match is confirmed, the tool conducts read-only checks before initiating the actual decryption sequence. Every stage is logged meticulously for transparency and compliance validation.
Requirements Before Running the Decryptor:
To begin the recovery process safely, victims must have:
- The ransom note (How_to_recover_your_files.txt) in its original form
- Several encrypted samples bearing the .monkey extension
- Administrator privileges on the compromised system
- A stable internet connection for secure cloud-side key verification, if required
Essential Actions Right After a Monkey Ransomware Attack
Responding promptly and methodically can drastically improve your chances of recovery.
First, immediately isolate the infected machines from the network and all shared storage. This halts further propagation and limits encryption damage.
Second, ensure all affected files and ransom notes are left untouched — renaming or opening them could hinder later decryption.
If you’re operating virtual machines or large-scale infrastructure, consider a controlled shutdown to prevent continued encryption or outbound data leaks.
Finally, bring in digital forensics or incident response specialists. They can help capture volatile data such as RAM dumps, analyze process activity, and retrieve firewall and proxy logs needed for later attribution.
Restoring Files Encrypted by Monkey Ransomware
Free Recovery Options
Backup Restoration:
If your organization maintains offline, cloud-isolated, or immutable backups, they represent the best chance of full data restoration. Always verify each backup before reusing it. Confirm its cleanliness through checksum validation or isolated mounting, as ransomware often corrupts connected drives and shadow copies.
VM Rollback from Snapshots:
If virtual environments (like VMware or Hyper-V) have pre-attack snapshots, these can restore systems in minutes. However, confirm through snapshot logs that the attacker didn’t delete or modify these restore points.
Paid and Professional Recovery Methods
While it might be tempting, paying a ransom should only ever be a last resort. Even after payment, attackers may fail to deliver a valid decryptor — or worse, re-encrypt your environment later. Ransom transactions also fund cybercrime and can breach local or international regulations.
When all other methods fail, negotiation may occur through professional intermediaries under legal and insurance guidance.
Our service provides technical recovery without enabling criminals. After analyzing encrypted samples, we perform a proof-of-concept (PoC) decryption to confirm variant compatibility. Once verified, our team executes the full-scale restoration in a forensically sound and logged environment. This ensures file authenticity and complete auditability.
How to Use Our Monkey Decryptor — Complete Step-by-Step Guide
Contain and Isolate
Begin by disconnecting infected devices from networks and cloud synchronization points. Unmount any connected drives or shared folders to prevent cascading encryption.
Preserve Critical Evidence
If possible, perform a disk image of the affected system. If full imaging isn’t possible, copy the ransom note and multiple encrypted files onto an offline USB or secure medium. Never alter originals — maintain metadata and timestamps.
Document the Ransom Note
Keep the How_to_recover_your_files.txt ransom note in its exact location. Take screenshots of its content, and record file timestamps. Create SHA-256 hashes for both the note and encrypted file samples to maintain forensic integrity.
Choose Representative Encrypted Files
Select two to four small, non-sensitive encrypted files (e.g., .docx, .jpg, .txt) for analysis. Use copies only. This ensures safety while our analysts test variant compatibility.
Contact Our Response Team
Use our verified secure channel rather than any contact information in the ransom note. Provide an incident overview — affected systems, ransom note filename, infection timeline, and a contact person for follow-up. We’ll reply with upload instructions for secure file transfer.
Upload Samples and Hashes Securely
Upload the ransom note and encrypted file samples using the provided secure portal. Include the Victim ID (if present) and pre-computed hashes.
Proof-of-Concept (PoC) Decryption Phase
Our analysts identify your variant and attempt a limited-scope decryption on 1–2 files. Once successful, you’ll receive the decrypted samples and integrity logs for verification before moving to the full restoration phase.
Authorize the Full Recovery
After validating the PoC results, sign the engagement terms covering scope, pricing, confidentiality, and service window. We’ll coordinate working hours and throttle limits to avoid interrupting live operations.
Execute Full Decryption Safely
The decryptor performs final validation before file restoration. The process is monitored continuously, and logs are generated automatically for auditing.
Verify and Confirm Results
Once decryption finishes, validate the recovered data using checksums or by opening critical files in isolated systems. Retain the full integrity report and recovery log as part of your compliance record.
Post-Recovery Cleanup and Security Reinforcement
After restoration, remove all remaining ransomware components. Rebuild affected systems if persistence indicators are found. Update passwords, patch vulnerabilities, and review access control on backup systems to prevent recurrence.
Understanding Monkey Ransomware
The Monkey ransomware is a data-locking malware strain that surfaced through submissions on VirusTotal. It encrypts files, adding a .monkey suffix (e.g., report.pdf.monkey, photo.png.monkey), and delivers a ransom note titled How_to_recover_your_files.txt.
This message informs victims that their backups are deleted, their data exfiltrated, and a payment is demanded for recovery. Victims are offered one free decryption as “proof” before being threatened with public data exposure or sale if they refuse to pay within 24 hours.
It’s essential to understand that while removing the malware stops further encryption, it does not decrypt the files already compromised. Only secure backups or a legitimate decryptor can restore them safely.
Name, Extensions & Ransom-Note Information
Ransomware Name: Monkey virus (crypto-locker category)
Encrypted File Extension: .monkey (e.g., 1.jpg.monkey)
Ransom Note Filename: How_to_recover_your_files.txt
Ransom Note ExcerptHello,
If you’re reading this, your company’s network is encrypted and most backups are destroyed. We have also exfiltrated a significant amount of your internal data.
ATTENTION! Strictly prohibited:
– Deleting or renaming encrypted files;
– Attempting recovery with third-party tools;
– Modifying file extensions.
Any such actions may make recovery impossible.
What you need to know:
1. Contact us at [email protected] within 24 hours.
2. Payment after 24 hours will be increased.
3. We offer you a test decryption and proof of data exfiltration.
4. If no agreement is reached, your data will be sold and published.
We’re open to communication, but there will be no negotiations after deadline.
Your only chance to get your data back and avoid data leak is to follow our instructions exactly.

IOCs, Attack Tactics, and Tools Observed
Indicators of Compromise (IOCs)
- Ransom Note: How_to_recover_your_files.txt
- Encrypted Extension: .monkey
- Contact Address: [email protected]
- Common Antivirus Detections:
- Avast — MalwareX-gen [Misc]
- Combo Cleaner — Gen:Heur.Ransom.REntS.Gen.1
- ESET — Variant Of Generik.FXIBBWE
- Kaspersky — Trojan.Win32.DelShad.osy
- Microsoft — Ransom:Win64/MonkeyCrypt.PB!MTB
- Avast — MalwareX-gen [Misc]
Tactics, Techniques & Procedures (TTPs)
Initial Intrusion: Typically achieved via malicious email attachments, infected torrent downloads, or deceptive online ads.
Execution: Encrypts reachable files, adding the .monkey suffix.
Extortion: The ransom note claims data theft and backup deletion, using time-sensitive threats (24-hour escalation) to pressure payment.
Post-Infection Behavior: Some builds may deploy secondary payloads such as password stealers or remote-access trojans.
Tools Used by Attackers
- Delivery through infected executables, archives, or document macros.
- Anonymous onion-mail services for communication.
- Cryptocurrency wallets (Bitcoin) for ransom collection.
- Additional payloads — credential theft tools or RATs — occasionally accompany the main ransomware binary.
Victim Landscape — Global Impact
Top affected countries
Top affected sectors
Timeline

Conclusion
Monkey ransomware continues to evolve, combining file encryption with data-leak threats to increase pressure on victims. Paying the ransom remains unreliable and unethical — instead, focus on containment, forensic preservation, and validated decryption methods.
Always seek professional recovery, maintain multiple backups across locations, and harden your infrastructure against lateral movement. In ransomware incidents, swift and informed action often means the difference between total loss and complete restoration.
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