“Your personal files are encrypted by CTB Locker”: decrypt and remove ransomware virus

Be updated on all known editions of CTB-Locker, a nasty crypto ransomware program encoding victims’ data and extorting Bitcoins in exchange for decryption.

According to the threat actors’ ads posted on darknet forums back in 2014, CTB is an acronym for “Curve-Tor-Bitcoin”. This malicious file-encrypting entity is a real old stager on the cyber blackmail arena. It was the first Trojan of its kind that introduced built-in affiliate support, which means that this sample pioneered in the Ransomware-as-a-Service (RaaS) domain. Even though the most massive propagation campaign for its predecessor CryptoLocker ended via the FBI’s Operation Tovar two years ago, the same cybercriminal group stayed on this well-trodden track and crafted the new, more advanced sample in question. CTB Locker is known for concurrent circulation of multiple copycats, but they are all equally harmful because the code is shared among several syndicates in Eastern Europe.

With some external differences across these ransomware versions in place, the invariable thing is the AllFilesAreLocked alert displayed to victims, which is a BMP item that replaces the desktop background. It says, “Your personal files are encrypted by CTB-Locker. Your documents, photos, databases and other important files have been encrypted with strongest encryption and unique key, generated for this computer. Private decryption key is stored on a secret Internet server and nobody can decrypt your files until you pay and obtain the private key.” This warning message also displays a countdown script that shows the amount of time left from the original payment deadline of 96 hours. The malware operators want 0.2 Bitcoin, or about 130 USD, for the file recovery assistance. This sum may vary as different distributors have different mercantile appetites. Up to 5 files can be decrypted for free.

Having intruded on a Windows machine through a malicious file attached to a phishing email, CTB Locker scans all local drives for popular types of data and then applies elliptic curve cryptography (ECC) to encrypt all those files. The earlier versions of this hoax would append the .CTBL or .CTB2 extension to encrypted files. Later on, though, the perpetrators switched to the use of random extensions. The Trojan also drops icons for ransom payment instructions on the desktop and adds those to every folder with ciphered data. Along with the above-mentioned BMP image, these are named DecryptAllFiles [victim ID].txt and [random].html. Ultimately, the victim is redirected to a Tor page designed to accept and process the ransom payments.

The encryption used by CTB Locker is too strong to get around, furthermore the malefactors implemented it immaculately. Recently, a new iteration appeared that encrypts the content of websites and demands 0.4 Bitcoin for the private key. This is one of the most sophisticated strains to date. The best-case scenario is where the user or webmaster has backups of their important data, in which case they can simply remove the ransomware and download unaffected copies of files from an offsite storage. Otherwise, there are two options: to pay up, or try to use workarounds below.

CTB Locker ransomware automated removal and data recovery

Owing to an up-to-date database of malware signatures and intelligent behavioral detection, the recommended software can quickly locate the infection, eradicate it and remediate all harmful changes. So go ahead and do the following:

1. Download and install the antimalware tool. Open the solution and have it check your PC for PUPs and other types of malicious software by clicking the Start Computer Scan button

Download CTB Locker virus remover

2. Rest assured the scan report will list all items that may harm your operating system. Select the detected entries and click Fix Threats to get the troubleshooting completed.

Data recovery toolkit to the rescue

Some strains of ransomware are known to delete the original files after the encryption routine has been completed. As hostile as this activity appears, it can play into your hands. There are applications designed to revive the information that was obliterated because of malfunctioning hardware or due to accidental removal. The tool called Stellar Data Recovery features this type of a capability and therefore it can be applied in ransom attack scenarios to at least get the most important files back. So use the app to get an idea of what data can be restored and let it do the recovery job. Here is a step-by-step walkthrough:

1. Download and install Stellar Data Recovery.

Download Stellar Data Recovery

2. Open the application, select the types of recoverable files to look for, and click Next.

3. Choose the areas you want the tool to recover from and click the Scan button.

4. Having scanned the specified locations, the program will display a notification about the total amount of recoverable data. Close the dialog and click the Recover button. This will hopefully help you get some of your valuable files back.

Ransomware Prevention Tips

To avoid CTB Locker ransomware and other file-encrypting infections in the future, follow several simple recommendations:

These techniques are certainly not a cure-all, but they will add an extra layer of ransomware protection to your security setup.

Revise your security status

Post-factum assessment of the accuracy component in malware removal scenarios is a great habit that prevents the comeback of harmful code or replication of its unattended fractions. Make sure you are good to go by running an additional safety checkup. Another benefit of using the antimalware tool is that it will keep ransomware threats from intruding on your computer further on.

Download CTB Locker ransomware removal tool