TOR13 Ransomware

Also Known As: TOR13 virus
Distribution: Low
Damage level: Severe

TOR13 ransomware removal instructions

What is TOR13?

Belonging to the Dharma family, TOR13 is yet another ransomware-type infection discovered by Jakub Kroustek. After stealthily infiltrating the system, TOR13 encrypts most stored files using RSA-1024 cryptography. In doing so, TOR13 appends filenames with the victim's unique ID, developer's email address, and the ".TOR13" extension. For example, "sample.jpg" might be renamed to a filename such as "[].TOR13". Compromised data immediately becomes unusable. TOR13 is also designed to open a pop-up window and place the "RETURN FILES.txt" text file on the desktop.

The new text file contains a short message stating that data is compromised and that victims should contact developers via an email address provided. The pop-up, on the other hand, gives much more detail. It is stated that data is encrypted using the RSA-1024 algorithm. This cryptography is asymmetric and, thus, each victim receives two different keys: public (encryption) and private (decryption). Restoring data without the private key is impossible. Cyber criminals store all keys on a remote server and victims cannot access them, unless a ransom is paid. Therefore, victims must submit payment to recover their data. The cost is not specified (all details are provided via email), however, it is stated that the ransom must be paid within seven days after encryption, otherwise the key is permanently deleted (overwritten by other users' keys). Victims are also permitted to attach one encrypted file (up to 1 MB, non-archived) that does not contain any valuable information. Criminals then decrypt the attached file and return it as 'proof' and a guarantee that decryption is possible and that these people can be trusted. In fact, this is often a scam. Ransomware developers usually ignore victims once they receive payment. Therefore, paying usually gives no positive result and users are scammed. No matter what the cost, do not pay. Unfortunately, there are no tools capable of cracking TOR13 encryption and restoring data free of charge. The only solution is to restore everything from a backup.

Screenshot of a message encouraging users to pay a ransom to decrypt their compromised data:

TOR13 decrypt instructions

The internet is full of ransomware-type infections that share similarities with TOR13 (e.g., Mcold, Dotmap, DDOS, etc.). Although the developers are different, virtually all ransomware-type infections have identical behavior - they compromise data (typically, by encryption) so that developers can then blackmail victims by offering recovery of files in return for payment. In addition, infections of this type often use RSA, AES, and other similar algorithms that generate unique decryption keys. Therefore, unless the virus is still in development or has certain bugs/flaws, restoring data manually without involvement of developers (contacting these people is not recommended) is impossible. Infections such as TOR13 present a strong case for maintaining regular backups, however, store them on remote servers/unplugged storage devices, since locally stored backups are compromised together with regular data. Note that there is always a chance that servers and storage devices can be damaged and, therefore, have multiple backup copies stored in different locations.

How did ransomware infect my computer?

The way developers proliferate TOR13 is currently unconfirmed, however, infections of this type are usually distributed using trojans, fake software cracks/updaters, third party software download sources, and spam email campaigns. Trojans are essentially malicious applications that stealthily infiltrate computers and download/install additional malware. Cracking tools activate paid software free of charge, however, most are fake - developers use them to proliferate malware. Therefore, users are much more likely to infect their computers rather than gain access to paid features. Fake updaters infect computers by downloading/install malware rather than updates, or by exploiting outdated software bugs/flaws. Peer-to-peer (P2P) networks, free file hosting sites, freeware download websites and other similar sources are used to present malicious executables as legitimate software. Users are simply tricked into manual download/installation of malware. Spam email campaigns are also used in a similar manner. Criminals send hundreds of thousands of emails that contain malicious attachments (links/files) and deceptive messages encouraging users to open them. Criminals are also likely to present these attachments as important documents (e.g., bills, invoices, etc.) in attempts to give the impression of legitimacy. In summary, the main reasons for computer infections are poor knowledge of these threats and careless behavior.

Threat Summary:
Name TOR13 virus
Threat Type Ransomware, Crypto Virus, Files locker
Encrypted Files Extension .TOR13 (this ransomware also appends filenames with the victim's unique ID and developer's email address).
Ransom Demanding Message Pop-up window, RETURN FILES.txt text file.
Cyber Criminal Contact,
Detection Names (expiorer321.exe) Avast (Win32:Malware-gen), BitDefender (Trojan.Ransom.Crysis.E), ESET-NOD32 (a variant of Win32/Filecoder.Crysis.P), Kaspersky (, Full List Of Detections (VirusTotal)
Symptoms Cannot open files stored on your computer, previously functional files now have a different extension (for example, my.docx.locked). A ransom demand message is displayed on your desktop. Cyber criminals demand payment of a ransom (usually in bitcoins) to unlock your files.
Distribution methods Infected email attachments (macros), torrent websites, malicious ads.
Damage All files are encrypted and cannot be opened without paying a ransom. Additional password-stealing trojans and malware infections can be installed together with a ransomware infection.
Malware Removal (Windows)

To eliminate possible malware infections, scan your computer with legitimate antivirus software. Our security researchers recommend using Malwarebytes.
▼ Download Malwarebytes
To use full-featured product, you have to purchase a license for Malwarebytes. 14 days free trial available.

How to protect yourself from ransomware infections?

The key to computer safety is caution. Therefore, pay close attention when downloading/updating/installing software, and browsing the Internet in general. We advise you to download apps from official sources only, using direct download links. Third party downloaders/installers often include rogue apps, and thus such tools should never be used. You should update software using implemented functions or tools provided by the official developer only. Bear in mind that software piracy is a cyber crime and the risk of infection is extremely high. Therefore, never attempt to crack installed applications. Handle received email attachments with care. If the sender seems suspicious/unrecognizable, do not open anything. Irrelevant attachments should be ignored. Have a reputable anti-virus/anti-spyware suite installed and running. These tools detect and eliminate most infections before the system is harmed. If your computer is already infected with TOR13, we recommend running a scan with Malwarebytes for Windows to automatically eliminate this ransomware.

Text presented in TOR13 ransomware pop-up window:

You can send us up to 1 file for free decryption. The total size of files must be less than 1Mb (non archived), and files should not contain valuable information. (databases,backups, large excel sheets, etc.)
When you make sure of decryption possibility transfer the money to our bitcoin wallet. As soon as we receive the money we will send you:
1. Decryption program.
2. Detailed instruction for decryption.
3. And individual keys for decrypting your files.
Do not rename encrypted files.
Do not try to decrypt your data using third party software, it may cause permanent data loss.
Decryption of your files with the help of third parties may cause increased price (they add their fee to our) or you can become a victim of a scam.

Screenshot of TOR13 text file ("RETURN FILES.txt"):

TOR13 text file

Text presented within this file:

All your data is encrypted!
for return write to mail: or

Screenshot of files encrypted by TOR13 (".TOR13" extension):

Files encrypted by TOR13

TOR13 ransomware removal:

Instant automatic malware removal: Manual threat removal might be a lengthy and complicated process that requires advanced computer skills. Malwarebytes is a professional automatic malware removal tool that is recommended to get rid of malware. Download it by clicking the button below:
▼ DOWNLOAD Malwarebytes By downloading any software listed on this website you agree to our Privacy Policy and Terms of Use. To use full-featured product, you have to purchase a license for Malwarebytes. 14 days free trial available.

Quick menu:

Step 1

Windows XP and Windows 7 users: Start your computer in Safe Mode. Click Start, click Shut Down, click Restart, click OK. During your computer start process, press the F8 key on your keyboard multiple times until you see the Windows Advanced Option menu, and then select Safe Mode with Networking from the list.

Safe Mode with Networking

Video showing how to start Windows 7 in "Safe Mode with Networking":

Windows 8 users: Start Windows 8 is Safe Mode with Networking - Go to Windows 8 Start Screen, type Advanced, in the search results select Settings. Click Advanced startup options, in the opened "General PC Settings" window, select Advanced startup. Click the "Restart now" button. Your computer will now restart into the "Advanced Startup options menu". Click the "Troubleshoot" button, and then click the "Advanced options" button. In the advanced option screen, click "Startup settings". Click the "Restart" button. Your PC will restart into the Startup Settings screen. Press F5 to boot in Safe Mode with Networking.

Windows 8 Safe Mode with networking

Video showing how to start Windows 8 in "Safe Mode with Networking":

Windows 10 users: Click the Windows logo and select the Power icon. In the opened menu click "Restart" while holding "Shift" button on your keyboard. In the "choose an option" window click on the "Troubleshoot", next select "Advanced options". In the advanced options menu select "Startup Settings" and click on the "Restart" button. In the following window you should click the "F5" button on your keyboard. This will restart your operating system in safe mode with networking.

windows 10 safe mode with networking

Video showing how to start Windows 10 in "Safe Mode with Networking":

Step 2

Log in to the account infected with the TOR13 virus. Start your Internet browser and download a legitimate anti-spyware program. Update the anti-spyware software and start a full system scan. Remove all entries detected.

If you cannot start your computer in Safe Mode with Networking, try performing a System Restore.

Video showing how to remove ransomware virus using "Safe Mode with Command Prompt" and "System Restore":

1. During your computer start process, press the F8 key on your keyboard multiple times until the Windows Advanced Options menu appears, and then select Safe Mode with Command Prompt from the list and press ENTER.

Boot your computer in Safe Mode with Command Prompt

2. When Command Prompt mode loads, enter the following line: cd restore and press ENTER.

system restore using command prompt type cd restore

3. Next, type this line: rstrui.exe and press ENTER.

system restore using command prompt rstrui.exe

4. In the opened window, click "Next".

restore system files and settings

5. Select one of the available Restore Points and click "Next" (this will restore your computer system to an earlier time and date, prior to the TOR13 ransomware virus infiltrating your PC).

select a restore point

6. In the opened window, click "Yes".

run system restore

7. After restoring your computer to a previous date, download and scan your PC with recommended malware removal software to eliminate any remaining TOR13 ransomware files.

To restore individual files encrypted by this ransomware, try using Windows Previous Versions feature. This method is only effective if the System Restore function was enabled on an infected operating system. Note that some variants of TOR13 are known to remove Shadow Volume Copies of the files, so this method may not work on all computers.

To restore a file, right-click over it, go into Properties, and select the Previous Versions tab. If the relevant file has a Restore Point, select it and click the "Restore" button.

Restoring files encrypted by CryptoDefense

If you cannot start your computer in Safe Mode with Networking (or with Command Prompt), boot your computer using a rescue disk. Some variants of ransomware disable Safe Mode making its removal complicated. For this step, you require access to another computer.

To regain control of the files encrypted by TOR13, you can also try using a program called Shadow Explorer. More information on how to use this program is available here.

shadow explorer screenshot

To protect your computer from file encryption ransomware such as this, use reputable antivirus and anti-spyware programs. As an extra protection method, you can use programs called HitmanPro.Alert and EasySync CryptoMonitor, which artificially implant group policy objects into the registry to block rogue programs such as TOR13 ransomware.

Note that Windows 10 Fall Creators Update includes a "Controlled Folder Access" feature that blocks ransomware attempts to encrypt your files. By default, this feature automatically protects files stored in Documents, Pictures, Videos, Music, Favorites as well as Desktop folders.

Controll Folder Access

Windows 10 users should install this update to protect their data from ransomware attacks. Here is more information on how to get this update and add an additional protection layer from ransomware infections.

HitmanPro.Alert CryptoGuard - detects encryption of files and neutralises any attempts without need for user-intervention:

hitmanproalert ransomware prevention application

Malwarebytes Anti-Ransomware Beta uses advanced proactive technology that monitors ransomware activity and terminates it immediately - before reaching users' files:

malwarebytes anti-ransomware

  • The best way to avoid damage from ransomware infections is to maintain regular up-to-date backups. More information on online backup solutions and data recovery software Here.

Other tools known to remove TOR13 ransomware:

About the author:

Tomas Meskauskas

Tomas Meskauskas - expert security researcher, professional malware analyst.

I am passionate about computer security and technology. I have an experience of over 10 years working in various companies related to computer technical issue solving and Internet security. I have been working as an author and editor for since 2010. Follow me on Twitter and LinkedIn to stay informed about the latest online security threats. Contact Tomas Meskauskas.

PCrisk security portal is brought by a company RCS LT. Joined forces of security researchers help educate computer users about the latest online security threats. More information about the company RCS LT.

Our malware removal guides are free. However, if you want to support us you can send us a donation.

Malware activity

Global malware activity level today:

Medium threat activity

Increased attack rate of infections detected within the last 24 hours.

QR Code
TOR13 virus QR code
A QR code (Quick Response Code) is a machine-readable code which stores URLs and other information. This code can be read using a camera on a smartphone or a tablet. Scan this QR code to have an easy access removal guide of TOR13 virus on your mobile device.
We Recommend:

Get rid of Windows malware infections today:

Download Malwarebytes

Platform: Windows

Editors' Rating for Malwarebytes:
Editors ratingOutstanding!

[Back to Top]

To use full-featured product, you have to purchase a license for Malwarebytes. 14 days free trial available.