CTB-LOCKER Ransomware 🔐 (.CTBL File) — Removal Guide

The Ctb-locker virus belongs with the ransomware type of malicious agent. Ransomware of this type encrypts all user’s data on the PC (images, text files, excel sheets, audio files, videos, etc) and adds its own extension to every file, creating the DecryptAllFiles.txt files in each directory which contains the encrypted files.

It is better to prevent, than repair and repent!

When we talk about the intrusion of unfamiliar programs into your computer’s work, the proverb “Forewarned is forearmed” describes the situation as accurately as possible. Gridinsoft Anti-Malware is exactly the tool that is always useful to have in your armory: fast, efficient, up-to-date. It is appropriate to use it as an emergency help at the slightest suspicion of infection.

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What is Ctb-locker virus?

☝️ A strictly accurate description for the Ctb-locker is “a ransomware-type malicious agent”.

Ctb-locker appends its own .ctbl extension to every file’s name. For instance, an image entitled “photo.jpg” will be renamed to “photo.jpg.ctbl”. In the same manner, the Excel sheet with the name “table.xlsx” will be renamed to “table.xlsx.ctbl”, and so forth.

In each directory with the encrypted files, a DecryptAllFiles.txt text document will be found. It is a ransom money memo. Therein you can find information about the ways of paying the ransom and some other information. The ransom note most probably contains a description of how to buy the decryption tool from the ransomware developers. You can get this decoding tool after contacting Tor website through email. That is basically the scheme of the crime.

Ctb-locker abstract:

The DecryptAllFiles.txt file coming in package with the Ctb-locker malware provides the following frustrating information:

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. If you see the main locker window, follow the instructions on the locker. Otherwise, it\'s seems that you or your antivirus deleted the locker program. Now you have the last chance to decrypt your files.

1. Type the address hxxp://torproject.org in your Internet browser.
   It opens the Tor site.

2. Press \'Download Tor\', then press \'DOWNLOAD Tor Browser Bundle\',
   install and run it.

3. Now you have Tor Browser. In the Tor Browser open the hxxp://zaxseiufetlkwpeu.onion
   Note that this server is available via Tor Browser only.
   Retry in 1 hour if site is not reachable.

4. Copy and paste the following public key in the input form on server. Avoid missprints.
436VPT-XI445Z-X4CFSL-MPOT6U-PQL2TK-74RNAQ-XYCCWO-ADYDL6
27UGA3-4YIAVP-IF3TTK-YGXGAI-3FATAX-SFK2XJ-VMELOS-YQNMI7
Q456FO-OVG476-FXKES2-TIAVXZ-ME2RLY-OWBKKV-L7EWNS-KYSWLB
5. Follow the instructions on the server.

In the screenshot below, you can see what a directory with files encrypted by the Ctb-locker looks like. Each filename has the “.ctbl” extension added to it.

An example of encrypted .ctbl files.

How did my computer get infected with Ctb-locker ransomware?

There is a huge number of possible ways of ransomware infiltration.

There are currently three most exploited ways for tamperers to have ransomware planted in your system. These are email spam, Trojan infiltration and peer-to-peer file transfer.

If you access your inbox and see emails that look just like notifications from utility services companies, postal agencies like FedEx, Internet providers, and whatnot, but whose sender is unknown to you, be wary of opening those emails. They are most likely to have a ransomware file enclosed in them. So it is even riskier to open any attachments that come with letters like these.

Another thing the hackers might try is a Trojan virus model. A Trojan is an object that infiltrates into your PC disguised as something legal. For example, you download an installer for some program you need or an update for some program. However, what is unpacked turns out to be a harmful agent that encrypts your data. Since the installation wizard can have any title and any icon, you’d better be sure that you can trust the resource of the things you’re downloading. The optimal way is to use the software developers’ official websites.

As for the peer networks like BitTorrent or eMule, the danger is that they are even more trust-based than the rest of the Internet. You can never know what you download until you get it. Our suggestion is that you use trustworthy resources. Also, it is reasonable to scan the folder containing the downloaded objects with the antivirus as soon as the downloading is done.

How to remove the Ctb-locker virus?

It is important to note that besides encrypting your data, the Ctb-locker virus will most likely deploy Vidar Stealer on your machine to seize your credentials to various accounts (including cryptocurrency wallets). That spyware can extract your credentials from your browser’s auto-filling data.

Often racketeers would unblock some of your files to prove that they do have the decryption program. Since Ctb-locker virus is a relatively recent ransomware, security software engineers have not yet found a way to reverse its work. Nevertheless, the decoding tools are frequently updated, so the solution may soon be available.

Of course, if the hackers succeed in encoding victim’s essential files, the hopeless person will most likely fulfill their demands. Nevertheless, paying to racketeers does not necessarily mean that you’re getting your files back. It is still dangerous. After obtaining the ransom, the racketeers may send a wrong decryption code to the victim. There were reports about malefactors just disappearing after getting the money without even bothering to reply.

The best countermeasure to ransomware is to have aan OS restore point or the copies of your essential files in the cloud drive or at least on an external drive. Surely, that might be not enough. The most important thing could be that one you were working on when it all started. Nevertheless, it is something. It is also advisable to scan your PC for viruses with the anti-malware utility after the OS is rolled back.

Ctb-locker is not the only ransomware of its kind, since there are other specimens of ransomware out there that act in the same manner. Examples of those are Nifr, Boty, Niwm, and some others. The two basic differences between them and the Ctb-locker are the ransom amount and the encoding method. The rest is the same: documents become blocked, their extensions altered, ransom notes emerge in each folder containing encrypted files.

Some lucky users were able to decode the blocked files with the aid of the free software provided by anti-ransomware specialists. Sometimes the hackers mistakenly send the decryption key to the wronged in the ransom readme. Such an epic fail allows the victim to restore the files. But of course, one should never rely on such a chance. Make no mistake, ransomware is a criminals’ tool to pull the money out of their victims.

How сan I avoid ransomware infiltration?

Ctb-locker ransomware has no superpower, neither does any similar malware.

You can defend your system from its injection taking three easy steps:

• Never open any emails from unknown mailers with unknown addresses, or with content that has likely no connection to something you are waiting for (how can you win in a lottery without even taking part in it?). In case the email subject is more or less something you are waiting for, check all elements of the suspicious email carefully. A hoax letter will always contain mistakes.
• Avoid using cracked or untrusted programs. Trojans are often shared as a part of cracked products, possibly as a “patch” preventing the license check. Understandably, dubious programs are difficult to distinguish from reliable software, because trojans may also have the functionality you need. Try to find information on this program on the anti-malware message boards, but the best way is not to use such programs at all.
• And to be sure about the safety of the objects you downloaded, check them with GridinSoft Anti-Malware. This program will be a perfect armor for your PC.

Reasons why I would recommend GridinSoft¹

There is no better way to recognize, remove and prevent ransomware than to use an anti-malware software from GridinSoft².

Download Removal Tool.

You can download GridinSoft Anti-Malware by clicking the button below:

Run the setup file.

When setup file has finished downloading, double-click on the setup-antimalware-fix.exe file to install GridinSoft Anti-Malware on your system.

An User Account Control asking you about to allow GridinSoft Anti-Malware to make changes to your device. So, you should click “Yes” to continue with the installation.

Press “Install” button.

Once installed, Anti-Malware will automatically run.

Wait for the Anti-Malware scan to complete.

GridinSoft Anti-Malware will automatically start scanning your system for Ctb-locker infections and other malicious programs. This process can take a 20-30 minutes, so I suggest you periodically check on the status of the scan process.

Click on “Clean Now”.

When the scan has finished, you will see the list of infections that GridinSoft Anti-Malware has detected. To remove them click on the “Clean Now” button in right corner.

Frequently Asked Questions

🤔 How can I open “.ctbl” files?Is it possible to open“.ctbl” files?

Negative. That is why ransomware is so frustrating. Until you decode the “.ctbl” files you will not be able to access them.

🤔 What should I do to make my files accessible as fast as possible?

If the “.ctbl” files contain some really important information, then you probably have them backed up. If not, there is still a function of System Restore but it needs a Restore Point to be previously saved. All other solutions require time.

🤔 You have advised using GridinSoft Anti-Malware to get rid of the Ctb-locker virus. Does it mean that all my files, currently encrypted, will be removed too?

No way! The encrypted files are not harmful, so they won’t be deleted.

GridinSoft Anti-Malware only deals with actual viruses. The virus that has infiltrated your system is most likely still active and running scans every so often to arrest any new files you might create on your PC after the infection. As it has been mentioned above, the Ctb-locker virus comes with the company. It installs backdoors and keyloggers that can steal your account credentials and provide criminals with easy access to your system in the future.

🤔 What actions should I take if the Ctb-locker malware has blocked my computer and I can’t get the activation key.

If that happened, you need to have a flash memory drive with a pre-installed Trojan Killer. Use Safe Mode to perform the procedure. You see, the ransomware runs automatically as the system boots and encodes any new files created or imported into your machine. To block this function – use Safe Mode, which allows only the vital applications to run automatically. Consider reading our manual on booting Windows in Safe Mode.

🤔 What could help the situation right now?

Many of the encoded files might still be at your disposal

• If you exchanged your important files through email, you could still download them from your online mail server.
• You may have shared photographs or videos with your friends or family members. Just ask them to send those pictures back to you.
• If you have initially got any of your files from the Internet, you can try downloading them again.
• Your messengers, social networks pages, and cloud storage might have all those files as well.
• Maybe you still have the needed files on your old computer, a portable device, phone, memory stick, etc.

HINT: You can employ data recovery programs³ to retrieve your lost information since ransomware encodes the copies of your files, deleting the original ones. In the video below, you can learn how to use PhotoRec for such a recovery, but remember: you won’t be able to do it before you kill the ransomware itself with an antivirus program.

Also, you can contact the following governmental fraud and scam sites to report this attack:

• In the United States: On Guard Online;
• In Canada: Canadian Anti-Fraud Centre;
• In the United Kingdom: Action Fraud;
• In Australia: SCAMwatch;
• In New Zealand: Consumer Affairs Scams;
• In France: Agence nationale de la sécurité des systèmes d’information;
• In Germany: Bundesamt für Sicherheit in der Informationstechnik;
• In Ireland: An Garda Síochána;

To report the attack, you can contact local executive boards. For instance, if you live in USA, you can have a talk with FBI Local field office, IC3 or Secret Service.

1. GridinSoft Anti-Malware Review from HowToFix site: https://howtofix.guide/gridinsoft-anti-malware/
2. More information about GridinSoft products: https://gridinsoft.com/comparison
3. Here are Best Data Recovery Software Of 2023.