Tsar ransomware: what it is and how to remove it
Tsar ransomware is a type of malware that focuses on money extortion from victims after encrypting all pictures, documents, videos, music, databases, and other files on the targeted computers.
As pointed out by security researcher dnwls0719 on Twitter who first spotted the threat in the wild, it appends .Tsar extension to each of the files, and then drops "ReadME-Tsar.txt" ransom note on the desktop, as well as other folders on the system.
Facts checked October 6, 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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Tsar ransomware: summary
| Name | Tsar ransomware |
|---|---|
| Type | File locking virus, crypro-malware |
| Family | BlackHeart ransomware |
| First spotted | The virus was first spotted by security researcher dnwls0719 in late February 2020 |
| File extension | Each of the files is appended with .tsar marker after the encryption process with AES is complete |
| Main executable | SF.exe |
| 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 16 more facts
| Ransom note | A pop-up window shows up upon file encryption completion – it includes a timer which, upon expiration, will double the ransom demand. Additionally, ReadME-Tsar.txt is also dropped on the desktop – it includes more details about the attack |
|---|---|
| Contact | MR_Liosion@protonmail.com and Decrypt.Russ@protonmail.com |
| Data decryption | The only secure way to retrieve data without paying the attackers is using backups. If none are available other solutions include: using third-party recovery software (low success rate) paying ransomware authors (not recommended) waiting for the decryption tool to be developed |
| Detection names | No Microsoft detection name is known |
| Encrypted file extension | .tsar |
| 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 |
| Symptoms | Files renamed with a new extension, a ransom note left in folders and a Windows Security "Threats found" notification |
| Evidence | 5 write-ups by security sites; no sample analysed yet |
| Encrypted files | .tsar |
| Attacker contacts | MR_Liosion@protonmail.com |
| Free decryptor | No free decryptor is known (checked 6 October 2026) |
| First seen | 3 March 2020 |
| Microsoft Defender name | Trojan:MSIL/Filecoder.DSK!MTB |
| Facts checked | 6 October 2026 |
Tsar ransomware detection names
If Windows Security shows Trojan:MSIL/Filecoder.DSK!MTB, it has found Tsar ransomware or a file that belongs to it.
Write the name down before you click Remove: it is the most useful search term later, and you will need it if you report the incident.
A family name in the label is more informative than a heuristic one. Our page on why one threat has many antivirus names lists the common formats and what each part means.
- File extension:
.tsar - Note file:
ReadME-Tsar.txt - Contact:
MR_Liosion@protonmail.com
The Tsar ransomware note
You Are Crypted!
What's Happened to my computer?
You Are Crypted By RSA And AES And ChaCha20 Encryption And Not Recovered!
Your important files are encrypted.
Many of your documents,photo,video,database,project
and other files are no longer accessible because they have
been encrypted. maybe you are busy looking for a way to
recover your files, but do not waste your time. nobody can
recover your files without our decryption service. For Decrypting Email Me On ==>MR_Liosion@protonmail.com
For Decrypt pay
1000 $
Step 2: Complete form for get Decryption tools
My Email==>MR_Liosion@protonmail.com
mail Target
Write Your Email:
Request Decrypt
1000 $ Time Left ( Payment Will be raised to 2x )
How to remove Tsar ransomware
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 Tsar ransomware 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
Unplug the network cable or turn off Wi-Fi, and disconnect USB drives, external disks and network shares, so Tsar ransomware cannot reach more files. Pause OneDrive, Google Drive or Dropbox sync, because synced folders upload the encrypted copies over the good ones.
Leave the PC on but offline while you read the next steps, since a restart can let the ransomware run again. This applies to Windows 11 and Windows 10 alike.
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
Your files now end in
.tsarand the instructions are inReadME-Tsar.txt. Save both to a USB stick, a copy of the note and two small encrypted files, before anything else.On another device, check them with ID Ransomware or Crypto Sheriff: the family name decides which decryptor, if any, can help. Keep the note's ID and contact line for your report.
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
Our last check found that for Tsar ransomware, no free decryptor is known (checked 6 October 2026). Look again yourself in the No More Ransom list and the free decryptor pages of Emsisoft, Avast and Kaspersky, which add new families every year.
A decryptor needs the ransomware gone first, or it encrypts the files again. Keep at least one copy of the encrypted files on an external drive, even if no tool works yet.
Full procedure with screenshots: Ransomware: first steps, finding a decryptor and recovering files
Step 4: Remove the ransomware before you restore or decrypt
Removing Tsar ransomware does not bring the files back, but it has to come first. Start with Defender's Full scan, then the offline scan from the same Scan options page, which checks the disk before Windows loads.
If the scan cannot start, use Safe Mode with Networking. Delete the ransom notes only after you have saved a copy, because removal tools sometimes leave them behind on Windows 11 and 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
Windows keeps shadow copies for restore points and backups, and some ransomware fails to delete them.
vssadmin list shadowsin an administrator Command Prompt tells you at once whether any exist.If they do, right-click the folder that held your files, open Properties > Previous Versions, select a version from before the attack, and click Open to check it before you Restore or copy the files out. Windows 11 and Windows 10 both have the tab.
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
A backup made before the attack is the surest way back. Connect it only once the PC is clean, then restore from File History, Windows Backup, OneDrive's Restore your OneDrive or your own external copies.
Without a backup, try file recovery: the originals that Tsar ransomware deleted may still be on the disk until something overwrites them. Install nothing new on the drive you want to recover from on the Windows 11 or Windows 10 PC.
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 2020 · not reviewed since
Tsar ransomware - a file locking virus that threatens to delete decryption key after five days
Tsar ransomware is a type of malware that focuses on money extortion from victims after encrypting all pictures, documents, videos, music, databases, and other files on the targeted computers.
As pointed out by security researcher dnwls0719 on Twitter who first spotted the threat in the wild, it appends .Tsar extension to each of the files, and then drops "ReadME-Tsar.txt" ransom note on the desktop, as well as other folders on the system.
Additionally, Tsar virus also shows a pop-up window - it claims that the data was locked with the combination of RSA, AES, and ChaCha20 algorithms and that the only way to recover it is by paying the ransom of $1,000 in Bitcoin cryptocurrency.
Crooks behind Tsar ransomware claim that if they are not contacted via MR_Liosion@protonmail.com or Decrypt.Russ@protonmail.com emails within five days, the unique decryption key will be permanently deleted. While it is unclear whether such a scenario is plausible, paying threat actors is not recommended, and they might not send the required Tsar ransomware decryption tool.
Tsar ransomware stems from the BlackHeart malware family, which was first spotted back in April 2018. While the strain is not extremely prevalent, the attackers released a few versions over the years, including BlackRouter, Prodecryptor, and a few others. Despite low prevalence, those infected with Tsar ransomware can suffer devastating consequences, as the encryption algorithm used is secure, and no known free decryption tools are currently available.
Tsar file virus targets Windows operating systems and uses a variety of methods to reach them. For example, the attackers might employ malicious spam email attachments/hyperlinks to deliver the payload, as well as exploits, fake updates, software cracks, and other ways. To protect yourself from ransomware infections in the future, check the tips in our malware distribution paragraph below.
Before performing the data locking process, the Tsar virus also modifies Windows in a variety of ways, e.g., deletes Shadow Volume Copies to prevent easy data recovery, modifies Windows registry for persistence, drops a variety of malicious files, disables certain processes and services, etc.
Tsar ransomware typically targets the most common file types, such as .doc, .jpg, .txt, .dat, .mp4, .html, and others, although it skips the most vital Windows system files for it to operate. After the data locking process, a pop-up message shows up immediately, which reads:
While it is unknown whether the decryption tool will actually be deleted, many security experts recommend not trusting ransomware authors, as they might demand money after the first payment, or ignore the request completely. Instead, it is better to focus on the Tsar ransomware deletion process.
Most of the anti-malware solutions recognize the malicious executable SF.exe that populates the Tsar virus as follows:
It goes without saying that a comprehensive anti-malware can not only remove Tsar ransomware from the system but also protect it from its intrusion in the first place. As previously stated, there is no working decryption tool available, so the only safe method of data recovery is via backups.
Nevertheless, it is also important to mention that Tsar ransomware removal will not recover your data, as encryption is a separate process that occurs due to malware infection, but it is not reversible unless a unique key is acquired. Thus, simply backup locked files, get rid of malware with anti-virus software and only then try alternative recovery methods listed below.
- Trojan-Ransom.FileCrypter
- Ransomware-GMZ!E6491ED91A5A
- Mal/Ramsil-T
- Ransom.Tsar
- Generic.Ransom.WCryG.256E2920
- Trojan:MSIL/Filecoder.DSK!MTB
- Win32:RansomX-gen , etc.
From our report of Mar 2020 · not reviewed since
Apply comprehensive security measures to avoid ransomware infections
Ransomware is most definitely one of the most devastating malware types in the wild.
It is not only dangerous for home users who might lose precious personal photos or work files but also disastrous for corporations, businesses, and local governments. While the spread of the threat and the popularity of it has been rising in the past years, cybercriminals are constantly coming up with new ways of making victims pay ransoms.
For example, major ransomware distributors behind Maze, Sodinokibi, DoppelPaymer, Nemty, and others are now threatening to publish stolen sensitive information from its victims. Therefore, ransomware has huge implications, and the recovery process might be complicated (in some cases, data recovery might be completely impossible), so it is best not to get infected in the first place.
Security experts from Novirus.uk advice users to practice these precautionary measures in order to reduce the infection chances to a minimum:
Additionally, make sure you backup all your most important files on a cloud or an external storage device such as USB/external HDD.
- Employ next-gen security software with machine-learning and other advanced features that can prevent ransomware from entering;
- Update your operating system and all the installed apps as soon as security patches are deployed;
- Never download software cracks/keygens or pirated program installers;
- Do not allow an attachment acquired via a suspicious email to run macro commands ("Allow content") on your system;
- Enable anti-spam and anti-phishing tools, as well as ad-blocking extension;
- Protect all your accounts with secure alphanumeric passwords or use a password manager;
- Never use default TCP port for your Remote Desktop connections and disable the feature as soon as it is not used anymore.
From our report of Mar 2020 · not reviewed since
Delete Tsar ransomware securely
In many cases, users who get infected with ransomware do not know how to proceed next, and whether their files can be saved.
Because the Tsar virus does not have a working decryption tool, recovering data without paying criminals is highly unlikely, although not impossible. Therefore, you should remove Tsar ransomware and then try applying alternative methods we provide below; maybe ransomware failed to delete Shadow Volume Copies, and you will be able to retrieve everything with ShadowExplorer.
Nevertheless, before you perform Tsar ransomware removal, you should copy over all the encrypted data, as malware termination might permanently damage your data, and even threat actors will not be able to help you. Note that while there are many AV engines that detect the threat, not every anti-malware will be able to terminate the virus, so you might have to employ several removal tools.
[GI=method-1]In case of Tsar ransomware is tampering with your security software, access Safe Mode with networking as explained below:
[GI=method-2]System Restore can also be used when trying to get rid of the infection:
Data recovery software may sometimes be effective, as it may be able to extract working copies of some of your files on the hard drive.
Previous Windows Versions feature can help you with individual files
This method can only be used on files one-by-one, and only works if the System Restore point was established before ransomware struck.
ShadowExplorer method might suffice
In case of Tsar file virus failed to get rid of Shadow Volume Copies, this still should be able to retrieve most, if not all, of your files.
No decryption software is currently available
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.
Protect the files you restore
Restore only after the scans are clean and the PC no longer shows files that end in .tsar and no longer open; otherwise the restored copies can be damaged again.
Then build a backup that survives the next infection:
- one copy in the cloud with version history
- one on an external drive that is disconnected between backups
- the working copy on the PC
Version history matters because a backup that syncs damaged files overwrites the good ones.
How to do this with the tools built into Windows: the 3-2-1 backup rule on Windows.
Protect your privacy - employ a VPN
There are several ways how to make your online time more private - you can access an incognito tab.
However, there is no secret that even in this mode, you are tracked for advertising purposes. There is a way to add an extra layer of protection and create a completely anonymous web browsing practice with the help of VPN. This software reroutes traffic through different servers, thus leaving your IP address and geolocation in disguise.
Besides, it is based on a strict no-log policy, meaning that no data will be recorded, leaked, and available for both first and third parties. The combination of a secure web browser and VPN will let you browse the Internet without a feeling of being spied or targeted by criminals.
No backups? No problem. Use a data recovery tool
If you wonder how data loss can occur, you should not look any further for answers - human errors, malware attacks, hardware failures, power cuts, natural disasters, or even simple negligence.
In some cases, lost files are extremely important, and many straight out panic when such an unfortunate course of events happen. Due to this, you should always ensure that you prepare proper data backups on a regular basis.
If you were caught by surprise and did not have any backups to restore your files from, not everything is lost. is one of the leading file recovery solutions you can find on the market - it is likely to restore even lost emails or data located on an external device.
Questions about Tsar ransomware
How do I open .tsar files?
You cannot open them by renaming or with another program, because the content of files ending in .tsar has been encrypted. The only ways back are a working decryptor for the family, or clean copies from elsewhere:
- OneDrive versions
- File History
- an offline backup drive
- Previous Versions if the ransomware did not delete them
Identify the family first by uploading the ransom note and one encrypted file to ID Ransomware or No More Ransom. Avoid websites and programs that promise to open any encrypted file; they do not work and some are scams.
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.
Is there a free Tsar ransomware decryptor?
We last checked on 6 October 2026, and for Tsar ransomware no free decryptor is known. We check No More Ransom, which collects free tools from police and security companies, and the decryptor pages of the major antivirus vendors. A working decryptor exists only when the encryption has a flaw or the keys were leaked or seized.
Ignore sites and videos that offer a "Tsar ransomware decryptor" for download or for a fee: these are usually scams or malware. Real decryptors are free and come from known security companies or law enforcement. Keep the encrypted files in case a tool appears 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 Tsar ransomware get on my computer?
The way Tsar ransomware 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 .tsar 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.
Did Tsar ransomware steal my files or passwords?
We do not know yet. Nothing published so far shows data theft by Tsar ransomware, but the only confirmed sign is files that end in .tsar 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.
Is Tsar ransomware 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 ReadME-Tsar.txt tell me about the ransomware?
Quite a lot. The file name ReadME-Tsar.txt, 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.
What does the name Trojan:MSIL/Filecoder.DSK!MTB tell me?
Microsoft builds names in a fixed order:
- category
- then platform
- then family
- sometimes followed by a variant letter
- a suffix
The category is the most useful part for you. Trojan, Backdoor and PWS mean real malware that can download more, give remote access or steal passwords. PUA means unwanted software.
Ransom means ransomware. Suffixes such as !ml or !MTB mean the detection came from machine learning or behaviour analysis. Search for the family part of Trojan:MSIL/Filecoder.DSK!MTB together with the word Microsoft to find its entry in Microsoft's security encyclopedia.
Will Fortect remove Tsar ransomware?
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 Tsar ransomware, 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
- Virus Total: SF.exe (read October 6, 2026)
- Naked Security: 'Maze' ransomware threatens data exposure unless $6m ransom paid (read October 6, 2026)
- CISA: StopRansomware (read October 6, 2026)
- No More Ransom (read October 6, 2026)
- FTC: How to recognize, remove and avoid malware (read October 6, 2026)