Infected with CTB-Locker? Need to decrypt your files?
What is CTB-Locker
CTB-Locker (Curve-Tor-Bitcoin Locker) belongs to the family of ransomware viruses. It is also known as Critroni ransomware. This is also crypto-virus and it uses RSA-2048 encryption to encrypt sensitive files and folders. Usually CTB-Locker encrypts user documents, photos, music and other types of personal information. After this it asks for a ransom in bitcoins (0.3 or $120). CTB-Locker modifies file names and extensions of encrypted files. All affected files get .ctb or .ctb2 extension. There are some methods to decrypt .ctb files that will be shown below. Virus creates 3 files: AllFilesAreLocked.bmp, DecryptAllFiles.txt and randomly named HTML file. This files contain instructions for user to pay the random and decrypt files. CTB-Locker allows to decrypt 2 files for free, to show that decryption is possible. It is quite easy to remove CTB-Locker, but it is much harder to decrypt .ctb (.ctb2) files. Read instruction below to restore your files.
How CTB-Locker infected your PC
CTB-Locker is distributed using fake UPS notification emails with infected attachments. Once user unzips archived document and runs it, user will be shown message, that will ask to enable macros. This macros will download executable file and run it, encryption will start then. CTB-Locker will add .ctb or .ctb2 extension to all encrypted files. In this article you can learn how to decrypt .ctb files and remove CTB-Locker from your computer. The only way to protect your computer from such threats is to use antiviruses with crypto-protection like HitmanPro.Alert with CryptoGuard.
What to do if you are infected with CTB-Locker virus?
First of all don’t panic. Follow these easy steps below.
1. Start your computer in Safe Mode with networking. To do that, restart your computer, before your system starts hit F8 several times. This will stop system from loading and will show Advanced boot options screen. Choose Safe mode with networking option from the options list using up and down arrows on your keyboard and hit Enter.
2. Log in to the system infected with the CTB-Locker virus. Launch your Internet browser and download a reliable anti-malware program and start a full system scan. Once the scan is complete, review scan results and remove all entries detected.
Norton is a powerful removal tool. It can remove all instances of newest viruses, similar to CTB-Locker – files, folders, registry keys.
*Trial version of Norton provides detection of computer viruses for FREE. To remove malware, you have to purchase the full version of Norton.
Step 2: Remove following files and folders of CTB-Locker:
Remove following registry entries:
Remove following files:
How to decrypt files infected by CTB-Locker (.ctb files)?
Use automated decryption tools
There is ransomware decryptor from Kaspersky that may decrypt .ctb files decryption. It is free and may help you restore files encrypted by CTB-Locker. Download it from this page:
There is currently no automated decryption tool for CTB-Locker files, but that doesn’t mean that you need to pay the ransom. We track the topic and will add any new decryption tool available in this part of the article. Now you can try to use manual methods to restore and decrypt .ctb files.
Decrypt .ctb files manually
Restore the system using System Restore
Although, latest versions of CTB-Locker remove system restore files, this method may help you partially restore your files. Give it a try and use standard System Restore to revive your data.
- Initiate the search for ‘system restore‘
- Click on the result
- Choose the date before the infection appearance
- Follow the on-screen instructions
Roll the files back to the previous version
Previous versions can be copies of files and folders created by Windows Backup (if it is active) or copies of files and folders created by System Restore. You can use this feature to restore files and folders that you accidentally modified or deleted, or that were damaged (in our case – encrypted by CTB-Locker). This feature is available in Windows 7 and later versions.
- Right-click the file and choose Properties
- Open the Previous Version tab
- Select the latest version and click Copy
- Click Restore
Restore .ctb files using shadow copies
- Download and run Shadow Explorer.
- Select the drive and folder where your files are located and date that you want to restore them from.
- Right-click on folder you want to restore and select Export.
- Once the scanning process is done, click Recover to restore your files.
Protect your computer from ransomware
Most modern antiviruses can protect your PC from ransomware and crypto-trojans, but thousands of people still get infected. There are several programs that use different approach t protect from ransomware and lockers. One of the best is HitmanPro.Alert with CryptoGuard. You may already know HitmanPro as famous cloud-based anti-malware scanner. Check out ultimate active protection software from SurfRight.
Information provided by: Alexey Abalmasov