.Cerber3 file extension virus or Cerber3 ransomware virus: what it is and how to remove it
.Cerber3 is a file-encrypting virus which is considered to be an upgraded version of an infamous Cerber virus. It encodes data on the victimized computer with the help of sophisticated algorithms and appends .cerber3 extension afterward.
Facts checked October 7, 2026. Removal steps tested on Windows 11 (26H2) and checked against Microsoft's and the browser makers' current documentation. Sections marked as our earlier report are the original text: they describe the threat as it was then and have not been reviewed since. The 2026 status, the removal steps and the questions are current.
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.Cerber3 file extension virus or Cerber3 ransomware virus: summary
| Name | .Cerber3 file extension virus or Cerber3 ransomware virus |
|---|---|
| Type | Ransomware |
| Extension | .cerber3 |
| Ransom note | # HELP DECRYPT #.txt; the text is quoted in full below |
| Related versions | Cerber; Cerber 2.0; Cerber 3.0; Cerber 4.0; Cerber 5.0; Cerber 6.0 |
| Decryptable | No |
| Removal | Scan the PC with security software to find and remove the malware and anything installed with it. Fortect scans Windows for malware and repairs the system files and settings it damaged. Remove it nowTo use the full-featured product, you have to purchase a license for Fortect. The scan is free. |
Show 12 more facts
| Symptoms | After infection, files are locked, and the user is demanded to pay 1.24 Bitcoins for the decryption |
|---|---|
| Detection names | No Microsoft detection name is known |
| Contact | Not recorded in our earlier report |
| Encrypted file extension | .cerber3 |
| Decryptor | No free decryptor is known for this variant; check No More Ransom (nomoreransom.org) for updates |
| Distribution | Not recorded in the old report |
| Damage | Not recorded in the old report |
| Evidence | 5 write-ups by security sites; no sample analysed yet |
| Encrypted files | .cerber3 |
| Free decryptor | No free decryptor is known (checked 7 October 2026) |
| First seen | 21 March 2018 |
| Facts checked | 7 October 2026 |
What to search your PC and browser for
- File extension:
.cerber3 - Note file:
the ransom note
How .Cerber3 file extension virus or Cerber3 ransomware virus behaves
From our report of Mar 2018 · not reviewed since
Betabot is a trojan horse which helps to spread the ransomware worldwide
Beta bot is a dangerous trojan program that is designed to disable your antivirus systems and let inside other cyber threats or steal data.
Likewise, this malicious application is used in ransomware distribution techniques as well. Unfortunately, its elimination is extremely complicated, so you must take every precaution possible to avoid it in the first place.
You can infect your PC with this malware after visiting unsafe, suspicious or fake Internet pages, opening questionable emails or clicking on forged links. If you are ever unsure about the safety of the Internet website that you are going to visit, just do not enter it.
If you do not know the person who had sent you an email, do not open it, or its attachments. Keep your computer protected at all times.
Cyber criminals use new techniques now to deceive computer users, and several different ransomware prevention actions should be taken in order to protect the computer system from this virus. There are some tips on how you can protect your computer and your files from being impacted by ransomware virus:
- Install a good anti-malware software. It is the only one that can identify the ransomware and prevent it from invading the PC system without your knowledge.
- Keep all your programs up-to-date. It does not matter what sort of programs you have on your PC, make sure that they are all updated to their latest versions. It is a good idea to enable automatic updates - this way, these programs will be instantly updated as soon as their developer releases a new update.
From our report of Mar 2018 · not reviewed since
.Cerber3 is a dangerous crypto-malware infection
.Cerber3 is a file-encrypting virus which is considered to be an upgraded version of an infamous Cerber virus.
It encodes data on the victimized computer with the help of sophisticated algorithms and appends .cerber3 extension afterward. Users are informed about the attack in # HELP DECRYPT #.txt ransom note which demands to pay for the decryption tool in Bitcoins. Unfortunately, experts warn that paying the ransom is not a wise decision.
While the previous versions of Cerber3 ransomware are decryptable, this file-encrypting virus which is lurking in the cyberspace since 2016 is still undecryptable. However, there are still ways how you can get back the access to your files without making the transaction to the crooks.
In order to get back their files, crooks claim that people have to transfer some Bitcoins via particular payment website. However, paying the ransom is not as easy as you may think at first. Victims can access this site only via Tor browser which provides anonymity.
The ransom note of .Cerber3 informs its victims about the attack and provides a brief explanation of what data encryption is. Criminals attach multiple personalized Tor Browser links at the end of the message for the user to receive further information. Although remember, you should NOT pay the ransom.
An extract from Cerber3's ransom note:
While reaching out for your credit card, think whether you want to pay that ransom . We understand that you need your personal files and that they are very important to you, but remember that cyber criminals are people that are not worth your trust. Do you believe that they actually provide the decryption program and that it is going to be malware-free?
Sadly, cybercriminals might send a malicious component alongside the decryption software, making your computer vulnerable and exposed to risks. Besides, another reason not to pay is the fact that cybercriminals continue their malicious activities only because victims keep paying them.
Instead, you should fight back and not pay up! Remove .Cerber3 file extension virus from the system and do everything to prevent a repetition of such situation. Malware researchers might be able to create a free decryption tool soon, so we definitely do not recommend you to waste your money by paying these crooks.
A professional antivirus program will help you to eliminate this dangerous cyber threat from your system. Note that this is the easiest way to uninstall the ransomware since the security software will do all the job for you.
Additionally, after you get rid of .Cerber3, make sure to check the decryption instructions attached at the end of this article. There you will find multiple ways which might help to recover individual or all files which have been encrypted by the malware. Make sure to try them all to find the best solution for you.
The .Cerber3 file extension virus or Cerber3 ransomware virus ransom note
C_E_R_B_E_R R_A_N_S_O_M_W_A_R_E
Cannot you find the files you need?
Is the content of the files that you looked for not readable???
It is normal because the files' names, as well as the data in your files have been encrypted.
Great!
You have turned to be a part of a big community "#Cerb3r Ransomware".
How to remove .Cerber3 file extension virus or Cerber3 ransomware virus
Tools you'll need
All of these are free except where noted. Download them on a clean device if the infected PC is offline.
- A USB stick: to keep the ransom note, two or three encrypted files and screenshots off the infected PC.
- Microsoft Defender Offline: built into Windows 11 and Windows 10; scans before Windows starts, so running malware cannot hide.
- Microsoft Safety Scanner: a second, portable scanner with current signatures; each download works for 10 days.
- ID Ransomware: identifies the family from the note and one encrypted file and says whether a decryptor exists.
- No More Ransom: the free decryptors from police and security companies; check it again every few months.
- Fortect (optional): scans Windows for malware and repairs the system files and settings it damaged. The free scan is in the box above.
How to remove .Cerber3 file extension virus or Cerber3 ransomware virus and get your files back
Work in this order.
Disconnecting comes first, removal comes before any restore, and nothing here asks you to contact the attackers.
Step 1: Disconnect the PC and unplug backup drives
.Cerber3 file extension virus or Cerber3 ransomware virus encrypts everything it can reach, including drives and shares you connect later. Cut the network first: cable out, or Wi-Fi off from the taskbar.
Then unplug every USB stick and backup disk and pause cloud sync, so the encrypted versions do not replace your online copies. Do not reconnect any of them until the ransomware is removed from the Windows 11 or Windows 10 PC.
Windows 11: turn off Wi-Fi to take the PC offline. Full procedure with screenshots: Ransomware: first steps, finding a decryptor and recovering files
Step 2: Save the ransom note and confirm the family
Copy
the ransom noteand one or two files ending in.cerber3to a USB stick, and leave the originals where they are.From another device, upload the note and a sample file to ID Ransomware or No More Ransom's Crypto Sheriff, which name the family from the note, the extension and the file structure.
Write down the contact address and your personal ID from the note, because a decryptor or the police may ask for them.
Warning: Never contact the attackers from the infected Windows 11 or Windows 10 PC.
Windows 11: the ransom note and encrypted files to copy for identification. Full procedure with screenshots: Ransomware: first steps, finding a decryptor and recovering files
Step 3: Check for a free decryptor
For .Cerber3 file extension virus or Cerber3 ransomware virus, no free decryptor is known (checked 7 October 2026).
Search the family name in the No More Ransom decryption tools list and in the free decryptors of Emsisoft, Avast and Kaspersky, because new tools appear years after an attack.
Important: Keep the encrypted files even if nothing works today, and do not pay before every free option is ruled out: payment does not guarantee a working key.
Decryptors run on Windows 11 and Windows 10, but only after the ransomware itself is removed.
Full procedure with screenshots: Ransomware: first steps, finding a decryptor and recovering files
Step 4: Remove the ransomware before you restore or decrypt
Restoring or decrypting files while .Cerber3 file extension virus or Cerber3 ransomware virus still runs lets it encrypt them again. Run a Full scan in Windows Security > Virus & threat protection > Scan options, then the Microsoft Defender Antivirus (offline scan).
If the ransomware blocks Windows Security, start Safe Mode with Networking and scan from there. Some families install a password stealer as well, so let both scans finish on Windows 11 or Windows 10.
Windows 11: Windows Security > Virus & threat protection > Scan options. Full procedure with screenshots: Run a Microsoft Defender Offline scan
Step 5: Look for shadow copies of the files
Open Command Prompt as administrator and run
vssadmin list shadows. If it lists copies dated before the attack, right-click a folder with encrypted files in File Explorer, choose Properties > Previous Versions, and open or restore a version from before that date.ShadowExplorer, a free tool, shows the same copies when the tab is empty or hidden. Most current families delete shadow copies, so an empty list is normal, but the check takes two minutes on Windows 11 or Windows 10.
Windows 11: vssadmin list shadows shows whether shadow copies exist. Full procedure with screenshots: Ransomware: first steps, finding a decryptor and recovering files
Step 6: Restore the files from a backup or recover deleted originals
Restore from an external backup, File History or OneDrive's version history, choosing a date before the attack. Connect the backup drive only after the scans are clean, or the ransomware encrypts it too.
If there is no backup, file recovery software can sometimes find the deleted originals, because some ransomware writes an encrypted copy and deletes the original file.
Stop writing to the drive and try recovery on Windows 11 or Windows 10 before new files overwrite the space.
Full procedure with screenshots: Recover deleted files (Recycle Bin, backups, OneDrive) On uGetFix
Instructions for each browser and system
The detailed steps for every browser and system this guide covers. Open the one you use.
Manual removal using Safe Mode
Important! →
Manual removal guide might be too complicated for regular computer users. It requires advanced IT knowledge to be performed correctly (if vital system files are removed or damaged, it might result in full Windows compromise), and it also might take hours to complete. Therefore, we highly advise using the automatic method provided above instead.
Step 1. Access Safe Mode with Networking
Manual malware removal should be best performed in the Safe Mode environment.
Windows 7 / Vista / XP
- Click Start > Shutdown > Restart > OK.
- When your computer becomes active, start pressing F8 button (if that does not work, try F2, F12, Del, etc. - it all depends on your motherboard model) multiple times until you see the Advanced Boot Options window.
- Select Safe Mode with Networking from the list.
Windows 10 / Windows 8
- Right-click on Start button and select Settings.
- Scroll down to pick Update & Security.
- On the left side of the window, pick Recovery.
- Now scroll down to find Advanced Startup section.
- Click Restart now.
- Select Troubleshoot.
- Go to Advanced options.
- Select Startup Settings.
- Press Restart.
- Now press 5 or click 5) Enable Safe Mode with Networking.
Step 2. Shut down suspicious processes
Windows Task Manager is a useful tool that shows all the processes running in the background. If malware is running a process, you need to shut it down:
- Press Ctrl + Shift + Esc on your keyboard to open Windows Task Manager.
- Click on More details.
- Scroll down to Background processes section, and look for anything suspicious.
- Right-click and select Open file location.
- Go back to the process, right-click and pick End Task.
- Delete the contents of the malicious folder.
Step 3. Check program Startup
- Press Ctrl + Shift + Esc on your keyboard to open Windows Task Manager.
- Go to Startup tab.
- Right-click on the suspicious program and pick Disable.
Step 4. Delete virus files
Malware-related files can be found in various places within your computer. Here are instructions that could help you find them:
- Type in Disk Cleanup in Windows search and press Enter.
- Select the drive you want to clean (C: is your main drive by default and is likely to be the one that has malicious files in).
- Scroll through the Files to delete list and select the following:
Temporary Internet Files
Downloads
Recycle Bin
Temporary files - Pick Clean up system files.
- You can also look for other malicious files hidden in the following folders (type these entries in Windows Search and press Enter):
%AppData%
%LocalAppData%
%ProgramData%
%WinDir%
After you are finished, reboot the PC in normal mode.
From our report of Mar 2018 · not reviewed since
Cerber3 virus elimination from the system
If you have never encountered a file-encrypting virus and merely interested in how to uninstall Cerber3 ransomware, we suggest you to write down some essential steps which should be taken prior to the elimination — keep backups of your system files and avoid visiting shady websites, downloading suspicious content or obtaining software illegally to protect your computer from ransomware attack.
In case you have already become a victim of this ransomware, remove .Cerber3 virus as soon as you can. It is highly NOT recommended to do it manually. Only advanced computer users and IT experts might be able to do it correctly. Our team advises using automatic malware removal software like , , or to remove the virus in a right way.
Instructions provided below will help you to start .Cerber3 removal since the virus might be robust enough to prevent you from installing a professional antivirus. For that, NoVirus.uk experts warn that you might need to boot your computer into Safe Mode by following the guide which is presented below.
[GI=method-1]Cerber3 file virus might prevent you from installing, updating and scanning the computer with a security software. They will help you to reboot your device and start the automatic removal.
[GI=method-2]Another method to force automatic .cerber3 file removal is presented below:
Although this is not the official decryption tool, this software might help you to recover your encrypted records. Instructions on how to use this program are provided below.
Use Windows Previous Versions method to restore files encrypted by .cerber3 file virus
If System Restore feature has been enabled on your PC, you might have a chance to recover your files using these instructions:
Try ShadowExplorer method to recover files encrypted by Cerber 3 virus
This method works only if virus authors forget to add delete-shadow-copies feature to the virus. It might not work, but you can still try:
Cerber3 decryptor is not created yet.
Report it and recover your files
Report it
Report the attack even if you do not expect the files back: insurers and banks ask for the report number, and police use the contacts in the note to link cases.
- United States
- FBI IC3 · FTC ReportFraud
- United Kingdom
- Report Fraud (formerly Action Fraud) · NCSC
- Australia
- ReportCyber (ASD)
- EU countries
- Europol: national reporting sites
Give the victim ID, the note and the date the files were encrypted. A business that holds personal data may also have to notify its data protection authority, in the EU within 72 hours.
Make the next attack harmless
.Cerber3 file extension virus or Cerber3 ransomware virus could only hurt the files that had no second copy, and the signs (files that end in .cerber3 and no longer open) showed exactly which ones those were. The 3-2-1 rule fixes that:
- three copies
- two media
- one disconnected
A practical version for a home PC: OneDrive or another cloud backup with version history, plus an external disk that you plug in once a week for File History and then unplug. Test a restore now and then by opening a few files from the backup on another device.
Details, schedules and what not to back up are in our 3-2-1 backup guide for Windows.
Access your website securely from any location
When you work on the domain, site, blog, or different project that requires constant management, content creation, or coding, you may need to connect to the server and content management service more often. The best solution for creating a tighter network could be a dedicated/fixed IP address.
If you make your IP address static and set to your device, you can connect to the CMS from any location and do not create any additional issues for the server or network manager that needs to monitor connections and activities. VPN software providers like can help you with such settings and offer the option to control the online reputation and manage projects easily from any part of the world.
Recover files after data-affecting malware attacks
While much of the data can be accidentally deleted due to various reasons, malware is one of the main culprits that can cause loss of pictures, documents, videos, and other important files.
More serious malware infections lead to significant data loss when your documents, system files, and images get encrypted. In particular, ransomware is is a type of malware that focuses on such functions, so your files become useless without an ability to access them.
Even though there is little to no possibility to recover after file-locking threats, some applications have features for data recovery in the system. In some cases, can also help to recover at least some portion of your data after data-locking virus infection or general cyber infection.
Questions about .Cerber3 file extension virus or Cerber3 ransomware virus
Is there a decryptor for .cerber3 files?
That depends on the family behind the .cerber3 extension, which this guide cannot confirm yet from the reports alone. Check No More Ransom and ID Ransomware with your ransom note and one encrypted file; they list families with free tools.
If none exists today, keep the encrypted files and a copy of the note on a separate drive, because decryptors are sometimes published months later after flaws are found or servers are seized. Never buy a decryptor from a website that is not the security company that made it.
How do I open .cerber3 files?
You cannot open them by renaming or by choosing another program. The .cerber3 ending shows that .Cerber3 file extension virus or Cerber3 ransomware virus encrypted the content, and only the matching key can reverse it.
Renaming a file back to .docx or .jpg changes nothing except the icon, and it can confuse a future decryptor, so leave the names as they are.
To get the content back, use a backup, an unencrypted copy elsewhere, or a decryptor listed on No More Ransom if one exists for .Cerber3 file extension virus or Cerber3 ransomware virus. Store the encrypted files on an external disk until then.
Did .Cerber3 file extension virus or Cerber3 ransomware virus steal my files or passwords?
We do not know yet. Nothing published so far shows data theft by .Cerber3 file extension virus or Cerber3 ransomware virus, but the only confirmed sign is files that end in .cerber3 and no longer open, which says nothing about what happened before.
Many current ransomware attacks copy files or run a password stealer first, so it is wise to act as if they did.
From a clean device, change the passwords that were saved in the browsers on this PC, starting with e-mail and banking, sign out of all sessions and turn on two-step verification. Watch bank statements and account activity for the next few weeks.
Should I pay the ransom?
We advise against it, and so do the FBI, Europol and national cyber agencies. Payment does not guarantee a working tool: some attackers never reply, some tools damage files, and some variants have no decryptor at all. Paying also funds further attacks and can make you a target again.
Before considering payment, try every recovery option in this guide and report the attack. Companies must involve their legal adviser and insurer, because payments to sanctioned groups can be illegal. If files are truly irreplaceable, store the encrypted copies and wait; decryptors sometimes appear later.
Can a data-recovery company decrypt my files for a fee?
Only if a decryptor already exists or the company pays the attackers for you. Some "ransomware recovery" services advertise that they can decrypt families with no known flaw; in practice they negotiate with the attackers and add their own fee. Others use the same free tools listed on No More Ransom.
Before you hire anyone, ask in writing how they will recover the files, whether they will contact the attackers and what happens if they fail. A legitimate service answers clearly. If a free decryptor exists for your family, you can run it yourself.
How did .Cerber3 file extension virus or Cerber3 ransomware virus get on my computer?
The way .Cerber3 file extension virus or Cerber3 ransomware virus spreads has not been documented yet, so look at your own recent activity. On home PCs, ransomware most often comes with cracked programs, game cheats, key generators and fake updates, or with an e-mail attachment that was opened.
On business networks, attackers usually log in through Remote Desktop with a stolen or guessed password. Think back to what was downloaded or installed in the days before files that end in .cerber3 and no longer open, and check the Downloads folder and Installed apps sorted by date. Keep anything suspicious for your report, but do not run it again.
Is .Cerber3 file extension virus or Cerber3 ransomware virus the same as other ransomware with a similar name?
Not necessarily. Ransomware names come from the file extension, the note or a word in the code, so unrelated families often end up with similar names, and one family can appear under several names. The difference matters: a decryptor or advice for one family does not fit another and can damage files.
Compare the ending added to your files and the exact name of the note with the summary table at the top of this guide, then upload the note and one encrypted file to ID Ransomware from a clean device. If the result names another family, follow the guide for that family instead.
What does the ransom note tell me about the ransomware?
Quite a lot. The file name the ransom note, the wording, the contact addresses and the format of the personal ID are typical for each family. Uploading the note together with one encrypted file to ID Ransomware or No More Ransom's Crypto Sheriff usually names the family within seconds.
That name decides your options: some families have free decryptors, some can be partially recovered, and some cannot be decrypted at all. The note's claims about stolen data should be taken seriously but not at face value.
Should I reinstall Windows after the .cerber3 attack?
Reinstalling removes the ransomware but not the encryption: your files ending in .cerber3 stay encrypted afterwards. So first copy the encrypted files and the ransom note to a separate drive, in case a decryptor appears later. Then decide:
- a clean-up with an offline scan is often enough for home PCs
- while a full reset is safer if remote access was involved
- scans keep finding new items
Restore your backups only after the PC is clean, and change passwords from another device.
Will Fortect remove .Cerber3 file extension virus or Cerber3 ransomware virus?
Fortect scans Windows for malware and unwanted programs and repairs the system files and settings they change, and its free scan shows what it finds on your PC before you decide anything.
For .Cerber3 file extension virus or Cerber3 ransomware virus, follow the plan above as well: the browser steps take back permissions and settings that no scanner treats as a threat, and uninstalling the program that brought it removes the source.
Run Microsoft Defender's full scan and, if anything was found, its offline scan as a second opinion. If the symptoms are gone after the plan and both scans are clean, there is nothing more to do.
Sources
- Kaspersky Labs: What is Beta Bot? Definition (read October 7, 2026)
- CISA: StopRansomware (read October 7, 2026)
- No More Ransom (read October 7, 2026)
- FTC: How to recognize, remove and avoid malware (read October 7, 2026)
- Microsoft Learn: Microsoft Defender Offline (read October 7, 2026)