What is Brain Cipher Ransomware?
Your files are encrypted, there is a ransom note on your desktop or in affected folders, and everything with a new extension is now inaccessible. You need to act intelligently right now — not just quickly. Read this article fully before doing anything, because the decisions you make in the next few minutes can significantly affect your recovery options. The guide at the bottom is your next step.
Brain Cipher is a sophisticated ransomware strain that emerged in mid-2024 and rapidly became one of the most high-profile ransomware threats of 2024 and 2025. It is based on leaked LockBit 3.0 source code — placing it in the same technical lineage as some of the most destructive ransomware in history. Brain Cipher achieved global notoriety in June 2024 when it successfully attacked Indonesia’s National Data Center (PDN), encrypting government data and disrupting services for over 200 government agencies — one of the most significant ransomware attacks on national government infrastructure ever documented. The attackers initially demanded an $8 million ransom before the Brain Cipher group eventually released a free decryption key for the Indonesian government after significant public pressure. Brain Cipher continues to operate as a ransomware family targeting private sector organizations globally, with attacks documented across healthcare, education, and financial services.
Brain Cipher Ransomware Short Overview
| Type | LockBit 3.0-based ransomware / Double extortion operation. Notable for the 2024 Indonesian National Data Center attack. Appends custom extensions to encrypted files. Targets both Windows and ESXi environments. |
| Symptoms | Files encrypted with appended custom extension and completely inaccessible. Ransom note (HOW_TO_UNLOCK.txt or similar) dropped on desktop and in every affected folder. Volume Shadow Copies deleted. Security tools disabled or interfered with. Wallpaper changed to ransom message. Possible data exfiltration before encryption completed. |
| Removal Time | Approximately 15 minutes for a full-system scan |
| Removal Tool | See If Your System Has Been Affected by malware
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How Did Brain Cipher Ransomware Get In?
Brain Cipher operators are patient, methodical attackers who typically spend days inside a network before triggering encryption. Here are the documented initial access vectors:
- Phishing emails with malicious attachments — Targeted phishing emails carrying malicious attachments — fake invoices, document files, or archive downloads — are the primary initial access vector. Malspam campaigns targeting specific industries are used to deliver the initial loader.
- Exploitation of internet-facing vulnerabilities — Brain Cipher operators actively exploit known vulnerabilities in internet-facing infrastructure. The Indonesian PDN attack exploited a Microsoft Windows Defender vulnerability. Every unpatched zero-day vulnerability in your exposed systems is a potential Brain Cipher entry point.
- Compromised RDP and VPN credentials — Internet-facing Remote Desktop Protocol servers and unpatched VPN appliances are exploited using stolen or brute-forced credentials, giving attackers direct network access for lateral movement using tools like Cobalt Strike.
- Software bundling and drive-by downloads — For individual users and smaller organizations, downloading freeware from unofficial sources through software bundling remains a delivery vector for the initial loader component.
What Does Brain Cipher Ransomware Do?
Brain Cipher is a full double-extortion ransomware operation. Here is the complete attack chain:
- Reconnaissance and lateral movement — After gaining initial access, operators map the network, harvest credentials using Mimikatz, and identify backup servers, domain controllers, and critical data repositories. Encryption is triggered only after maximum damage positioning is achieved.
- Data exfiltration for double extortion — Before any file is encrypted, sensitive data is silently exfiltrated to Brain Cipher’s infrastructure. This stolen data is then threatened to be published on their dark web leak site if the ransom is not paid — providing two simultaneous extortion levers even if the victim has functional backups.
- File encryption using LockBit 3.0 engine — The ransomware uses the LockBit 3.0 cipher combining AES encryption and RSA encryption to lock files. A custom extension is appended to every encrypted file and a ransom note is placed in every affected directory with Tor Browser contact instructions. The decryption key is held exclusively by the attackers.
- Defense evasion and backup destruction — Volume Shadow Copies are deleted via WMIC commands, backup jobs are disabled, security tools are neutralized using BYOVD techniques, and registry key entries are modified for persistence. The ransomware contacts a remote C&C server to coordinate the attack and exfiltrate the encryption key.
A limited free decryptor was released for the Indonesian government attack variant — but this does not apply to all Brain Cipher variants or subsequent attacks. Always check nomoreransom.org first to see if a free decryptor exists for your specific variant before considering any other options. Do not pay the ransom without professional incident response guidance.
What Should You Do?
Isolate every affected system from the network immediately. Do NOT restart encrypted machines. Preserve all forensic evidence including the ransom note and any malware samples. Upload a sample of your encrypted files and the ransom note to id-ransomware.malwarehunterteam.com to confirm the exact Brain Cipher variant and check decryption availability. Check nomoreransom.org for any available free decryptors. Report to CISA, the FBI IC3 at ic3.gov, and relevant national authorities. Follow the complete removal and restore guide below this article for your best path forward.
Ventsislav Krastev
Ventsislav is a cybersecurity expert at SensorsTechForum since 2015. He has been researching, covering, helping victims with the latest malware infections plus testing and reviewing software and the newest tech developments. Having graduated Marketing as well, Ventsislav also has passion for learning new shifts and innovations in cybersecurity that become game changers. After studying Value Chain Management, Network Administration and Computer Administration of System Applications, he found his true calling within the cybersecrurity industry and is a strong believer in the education of every user towards online safety and security.
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Step 1: Scan for Brain Cipher Ransomware with SpyHunter Anti-Malware Tool
Ransomware Automatic Removal - Video Guide
Step 2: Uninstall Brain Cipher Ransomware and related malware from Windows
Here is a method in few easy steps that should be able to uninstall most programs. No matter if you are using Windows 10, 8, 7, Vista or XP, those steps will get the job done. Dragging the program or its folder to the recycle bin can be a very bad decision. If you do that, bits and pieces of the program are left behind, and that can lead to unstable work of your PC, errors with the file type associations and other unpleasant activities. The proper way to get a program off your computer is to Uninstall it. To do that:
Follow the instructions above and you will successfully delete most unwanted and malicious programs.
Step 3: Clean any registries, created by Brain Cipher Ransomware on your computer.
The usually targeted registries of Windows machines are the following:
- HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\Run
- HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run
- HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\RunOnce
- HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\RunOnce
You can access them by opening the Windows registry editor and deleting any values, created by Brain Cipher Ransomware there. This can happen by following the steps underneath:
Tip: To find a virus-created value, you can right-click on it and click "Modify" to see which file it is set to run. If this is the virus file location, remove the value.
Before starting "Step 4", please boot back into Normal mode, in case you are currently in Safe Mode.
This will enable you to install and use SpyHunter 5 successfully.
Step 4: Boot Your PC In Safe Mode to isolate and remove Brain Cipher Ransomware
Step 5: Try to Restore Files Encrypted by Brain Cipher Ransomware.
Method 1: Use STOP Decrypter by Emsisoft.
Not all variants of this ransomware can be decrypted for free, but we have added the decryptor used by researchers that is often updated with the variants which become eventually decrypted. You can try and decrypt your files using the instructions below, but if they do not work, then unfortunately your variant of the ransomware virus is not decryptable.
Follow the instructions below to use the Emsisoft decrypter and decrypt your files for free. You can download the Emsisoft decryption tool linked here and then follow the steps provided below:
1 Right-click on the decrypter and click on Run as Administrator as shown below:
2. Agree with the license terms:
3. Click on "Add Folder" and then add the folders where you want files decrypted as shown underneath:
4. Click on "Decrypt" and wait for your files to be decoded.
Note: Credit for the decryptor goes to Emsisoft researchers who have made the breakthrough with this virus.
Method 2: Use data recovery software
Ransomware infections and Brain Cipher Ransomware aim to encrypt your files using an encryption algorithm which may be very difficult to decrypt. This is why we have suggested a data recovery method that may help you go around direct decryption and try to restore your files. Bear in mind that this method may not be 100% effective but may also help you a little or a lot in different situations.
Simply click on the link and on the website menus on the top, choose Data Recovery - Data Recovery Wizard for Windows or Mac (depending on your OS), and then download and run the tool.
Brain Cipher Ransomware-FAQ
What is Brain Cipher Ransomware Ransomware?
Brain Cipher Ransomware is a ransomware infection - the malicious software that enters your computer silently and blocks either access to the computer itself or encrypt your files.
Many ransomware viruses use sophisticated encryption algorithms to make your files inaccessible. The goal of ransomware infections is to demand that you pay a ransom payment to get access to your files back.
What Does Brain Cipher Ransomware Ransomware Do?
Ransomware in general is a malicious software that is designed to block access to your computer or files until a ransom is paid.
Ransomware viruses can also damage your system, corrupt data and delete files, resulting in the permanent loss of important files.
How Does Brain Cipher Ransomware Infect?
Via several ways.Brain Cipher Ransomware Ransomware infects computers by being sent via phishing emails, containing virus attachment. This attachment is usually masked as an important document, like an invoice, bank document or even a plane ticket and it looks very convincing to users.
Another way you may become a victim of Brain Cipher Ransomware is if you download a fake installer, crack or patch from a low reputation website or if you click on a virus link. Many users report getting a ransomware infection by downloading torrents.
How to Open .Brain Cipher Ransomware files?
You can't without a decryptor. At this point, the .Brain Cipher Ransomware files are encrypted. You can only open them once they are decrypted using a specific decryption key for the particular algorithm.
What to Do If a Decryptor Does Not Work?
Do not panic, and backup the files. If a decryptor did not decrypt your .Brain Cipher Ransomware files successfully, then do not despair, because this virus is still new.
Can I Restore ".Brain Cipher Ransomware" Files?
Yes, sometimes files can be restored. We have suggested several file recovery methods that could work if you want to restore .Brain Cipher Ransomware files.
These methods are in no way 100% guaranteed that you will be able to get your files back. But if you have a backup, your chances of success are much greater.
How To Get Rid of Brain Cipher Ransomware Virus?
The safest way and the most efficient one for the removal of this ransomware infection is the use a professional anti-malware program.
It will scan for and locate Brain Cipher Ransomware ransomware and then remove it without causing any additional harm to your important .Brain Cipher Ransomware files.
Can I Report Ransomware to Authorities?
In case your computer got infected with a ransomware infection, you can report it to the local Police departments. It can help authorities worldwide track and determine the perpetrators behind the virus that has infected your computer.
Below, we have prepared a list with government websites, where you can file a report in case you are a victim of a cybercrime:
Cyber-security authorities, responsible for handling ransomware attack reports in different regions all over the world:
Germany - Offizielles Portal der deutschen Polizei
United States - IC3 Internet Crime Complaint Centre
United Kingdom - Action Fraud Police
France - Ministère de l'Intérieur
Italy - Polizia Di Stato
Spain - Policía Nacional
Netherlands - Politie
Poland - Policja
Portugal - Polícia Judiciária
Greece - Cyber Crime Unit (Hellenic Police)
India - Mumbai Police - CyberCrime Investigation Cell
Australia - Australian High Tech Crime Center
Reports may be responded to in different timeframes, depending on your local authorities.
Can You Stop Ransomware from Encrypting Your Files?
Yes, you can prevent ransomware. The best way to do this is to ensure your computer system is updated with the latest security patches, use a reputable anti-malware program and firewall, backup your important files frequently, and avoid clicking on malicious links or downloading unknown files.
Can Brain Cipher Ransomware Ransomware Steal Your Data?
Yes, in most cases ransomware will steal your information. It is a form of malware that steals data from a user's computer, encrypts it, and then demands a ransom in order to decrypt it.
In many cases, the malware authors or attackers will threaten to delete the data or publish it online unless the ransom is paid.
Can Ransomware Infect WiFi?
Yes, ransomware can infect WiFi networks, as malicious actors can use it to gain control of the network, steal confidential data, and lock out users. If a ransomware attack is successful, it could lead to a loss of service and/or data, and in some cases, financial losses.
Should I Pay Ransomware?
No, you should not pay ransomware extortionists. Paying them only encourages criminals and does not guarantee that the files or data will be restored. The better approach is to have a secure backup of important data and be vigilant about security in the first place.
What Happens If I Don't Pay Ransom?
If you don't pay the ransom, the hackers may still have access to your computer, data, or files and may continue to threaten to expose or delete them, or even use them to commit cybercrimes. In some cases, they may even continue to demand additional ransom payments.
Can a Ransomware Attack Be Detected?
Yes, ransomware can be detected. Anti-malware software and other advanced security tools can detect ransomware and alert the user when it is present on a machine.
It is important to stay up-to-date on the latest security measures and to keep security software updated to ensure ransomware can be detected and prevented.
Do Ransomware Criminals Get Caught?
Yes, ransomware criminals do get caught. Law enforcement agencies, such as the FBI, Interpol and others have been successful in tracking down and prosecuting ransomware criminals in the US and other countries. As ransomware threats continue to increase, so does the enforcement activity.
About the Brain Cipher Ransomware Research
The content we publish on SensorsTechForum.com, this Brain Cipher Ransomware how-to removal guide included, is the outcome of extensive research, hard work and our team’s devotion to help you remove the specific malware and restore your encrypted files.
How did we conduct the research on this ransomware?
Our research is based on an independent investigation. We are in contact with independent security researchers, and as such, we receive daily updates on the latest malware and ransomware definitions.
Furthermore, the research behind the Brain Cipher Ransomware ransomware threat is backed with VirusTotal and the NoMoreRansom project.
To better understand the ransomware threat, please refer to the following articles which provide knowledgeable details.
As a site that has been dedicated to providing free removal instructions for ransomware and malware since 2014, SensorsTechForum’s recommendation is to only pay attention to trustworthy sources.
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