Cowa Ransomware Decryptor
Our cybersecurity engineers have deconstructed the Cowa ransomware variant from the Makop family and engineered a robust decryptor. This specialized tool can retrieve encrypted data by leveraging the victim-specific ID and contact address embedded in the ransom note.
How Our Solution Works
By using advanced AI logic, our tool scans the ransom note to extract your unique ID and map it to the encrypted batch.
All decryption actions are conducted in a highly isolated, cloud-secured sandbox.
We also offer a universal decryptor variant for edge cases or unknown subtypes of Cowa.
What You’ll Need for Decryption
To initiate the decryption process, ensure the following are ready:
- Access to the +README-WARNING+.txt ransom file left by the malware
- All .cowa-locked files intact and unmodified
- A stable internet connection for secure upload
- Administrative permissions on the impacted systems
Essential First Actions Following a Cowa Ransomware Attack
Unplug Affected Devices
As soon as you discover an active Cowa infection, disconnect those machines from your network. This can prevent lateral propagation and safeguard backups.
Preserve All Forensic Evidence
Avoid deleting the ransom note or any encrypted files. Retain all relevant network logs, packet captures, and file hashes for investigation and future reference.
Avoid Restarting or Reformatting
Rebooting infected systems might re-trigger encryption processes. Formatting drives can eliminate any chance of recovering data—even with a decryptor.
Reach Out to Cyber Recovery Professionals
DIY decryption attempts often lead to data loss or corrupted files. The best course of action is to consult experienced recovery specialists right away.
Cowa Ransomware File Recovery and Decryption Explained
Cowa is a derivative of Makop ransomware and uses strong asymmetric encryption protocols. It renames affected files by appending a victim-specific string, the attacker’s email, and the .cowa extension. Without the private key held by the attackers, conventional decryption is impossible.
All Viable Recovery Methods
Offline Backups
If you maintain isolated, offline backups (e.g., on USB drives or non-networked devices), restoring from them is the cleanest and safest recovery method. These copies should pre-date the infection.
Shadow Copy Recovery
Windows systems often create Volume Shadow Copies—snapshot backups. If these have not been deleted by Cowa, you can recover files using Windows Restore. Time is of the essence, as Cowa typically deletes these copies using system commands.
Check Public Decryptor Repositories
Currently, no free decryptor supports .cowa. However, resources like NoMoreRansom.org and Kaspersky’s No Ransom Project occasionally release tools for older variants. It’s wise to monitor these platforms.
Paying the Ransom
This approach is widely discouraged. There’s no guarantee the attacker will send a working decryptor. Even when tools are delivered, many include bugs, spyware, or partial recovery outcomes. Moreover, ransom payments fund ongoing cybercrime.
Specialized ransomware negotiators can act on your behalf. They understand the psychology and behavior of ransomware groups and often negotiate for a lower ransom, ensure test decryptions are done first, and handle communications securely over Tor. However, their services can be costly and outcomes are not guaranteed.
Our Proprietary Cowa Decryption Tool
Our decryptor is engineered with precision. It maps your unique ransom ID to an internal key database, uploads encrypted files to an encrypted cloud environment, and decrypts them using isolated sandboxing. An integrity checker validates the results before returning your files. You only pay after success is verified.
Complete Cowa Ransomware Recovery Procedure Using Our Decryptor
Infection Verification
Check for .cowa extensions and the presence of the +README-WARNING+.txt file. These are hallmark signs of a Cowa infection.
Secure the System
Ensure affected machines are air-gapped and that no encryption processes are running in memory.
Submit to Our Team
Send encrypted samples and the ransom note to our support engineers. We’ll verify variant compatibility and issue a decryption plan.
Launch the Decryptor
Run our tool as an administrator. Input the victim ID from the ransom note and initiate the process. Files will be decrypted in the cloud and returned after thorough integrity validation.
Offline vs Online Recovery Options
Offline strategies—such as recovering from cold backups or shadow copies—are ideal for high-security or disconnected systems. Our online decryptor offers a faster path, using end-to-end encrypted transmission and expert oversight. Both options are fully supported.
Understanding Cowa Ransomware: A Makop Variant
Cowa is a Makop-based ransomware type that encrypts user files, renames them with a unique ID and attacker email, and appends the .cowa extension. It also alters the victim’s desktop wallpaper and leaves behind an intimidating ransom note file.
How Cowa Operates Internally
Cowa encrypts each file with robust AES-256 encryption via Windows API, often targeting document, image, and archive formats. It then renames files to include a unique identifier and contact email, for example:
invoice.pdf.[2AF20FA3].[[email protected]].cowa
It also drops +README-WARNING+.txt to issue threats and instructions.
Ransom Note Dissected: What It Says and Why It Matters
The text of the ransom note is carefully crafted to pressure the victim into fast compliance. It reads:
Your files are Stolen and Encrypted !!!
You need to contact us to get instructions. Your ID is listed below.
By contacting us you will receive a guarantee of the return of your files
and security from the publication of your files on the Internet.
Do not attempt to decrypt the data yourself, as this may result to file damage.
We guarantee success only if you contact us.
Other methods cannot provide a guarantee and will lead to the loss of your money.
Our email address: [email protected]
Contact us right away to decrypt the data
and avoid publishing your data on the Internet!
Tools and TTPs (Tactics, Techniques, and Procedures) Used by Cowa Operators
Initial Compromise
Access is often gained through vulnerable RDP endpoints. Brute-force tools like NLBrute.exe are used to guess passwords.
Reconnaissance and Spread
After access, threat actors use NS.exe, Everything.exe, and PowerShell scripts to scan the network, enumerate files, and identify backup systems.
Persistence
Makop actors use custom tools like PuffedUp and ARestore.exe to retain control and attempt credential recovery.
Privilege Escalation
The ransomware often exploits DLL side-loading and process injection techniques—classified under MITRE T1055 and T1574.002.
Evasion Techniques
Cowa avoids detection by skipping encryption on critical system files and applying string obfuscation. It also deletes Volume Shadow Copies using:
vssadmin delete shadows /all /quiet
This prevents users from restoring from system snapshots.
Encryption Process
The payload uses Windows APIs like CryptEncrypt and CryptGenRandom for AES-256 encryption. It then appends a .cowa extension to renamed files.
Tracking and Data Leakage
While Cowa doesn’t operate a public leak site, it uses IPLogger services to track victims who open the ransom note, confirming active infection and engagement.
Mapped MITRE ATT&CK® Techniques Used by Cowa
| Phase | Technique ID | Description |
| Initial Access | T1133 | Remote Desktop brute force |
| Execution | T1059 | PowerShell-based commands |
| Persistence | T1542.003 | Pre-OS Boot or DLL sideloading |
| Privilege Escalation | T1055 | Process injection |
| Defense Evasion | T1027 / T1490 | Obfuscation + Inhibit Recovery |
| Impact | T1486 | File encryption with data renaming |
These align directly with Cowa’s operational strategy—from initial compromise to encryption and ransom extortion.
How These Techniques Enable the Attack Lifecycle
- Initial Penetration: Gaining access via RDP brute-force
- Network Discovery: Scanning shares and sensitive directories
- Stealth and Evasion: Avoiding detection with obfuscated binaries
- Access Persistence: Ensuring re-entry or continued control
- File Lockdown: Encryption process starts silently, ends with ransom note
- Extortion Pressure: Threats of public data leaks and irreversible loss
Prevention and Mitigation Recommendations
- Disable macros and script execution in emails
- Train staff to identify phishing tactics
- Segment the network and apply firewall restrictions
- Keep antivirus signatures updated
- Enforce multi-factor authentication for RDP and VPN
- Use offline, immutable backups with regular versioning
- Regularly audit ports and patch remote access services
Global Impact and Attack Statistics: Cowa Ransomware
Countries Most Affected
Industries Impacted
Incident Growth Timeline
Conclusion
Cowa ransomware is powerful, but recoverable. With the right decryptor, methodical response, and trusted professionals, victims can reclaim their systems and data—without bowing to extortion. Whether you’re using backups or our decryptor, time and action are critical.
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