CDCC Virus (.cdcc Files Decrypt) + Ransomware Removal

Written by Brendan Smith

The Cdcc virus, also known as ransomware, is part of the STOP/DJVU family. This malware is notorious for its malicious file encryption capabilities. When the Cdcc virus gets into a computer, it targets various types of files, such as photos, videos, documents, and more. It modifies the file structure and adds the “.cdcc” extension to each file, making them inaccessible and unusable without the decryption.

Cdcc Virus Overview


🤔 Cdcc virus is ransomware that belongs to the DJVU/STOP family. Its main target is to encrypt your files. Then, this ransomware asks its victims to pay the ransom – ($999 – $1999) in Bitcoin.

The Cdcc virus is a malicious program that encrypts your files and coerces you into paying for their recovery. This ransomware ciphers a wide selection of file types. Encrypted files are identifiable by a distinct “.cdcc” extension. The affected files become inaccessible and unusable.

Subsequently, the ransomware demands a file decryption payment in Bitcoin from its victims, which ranges from $999 to $1999, depending on the time passed after the attack. Typically, a text file with ransom payment guidances is named “_readme.txt“.

Cdcc Ransomware operates by Salsa20 encryption algorithms to scramble the contents of the targeted files. Since the Cdcc virus uses such a strong encryption method, it becomes particularly difficult, if not impossible, to find the decryption key without the assistance of the attackers.

Once Cdcc malware finishes the encryption, it shows a ransom note to the user, demanding a ransom payment for the decryption key. The ransom note contains instructions on the ways of making the payment and also often contains threats of permanent data loss or increased ransom amounts if the ransom is not paid within a specified timeframe.

I have made a comprehensive list of potential solutions, advice, and approaches to remove the Cdcc ransomware and decrypt your files. In some cases, it may be possible to restore your files, but sometimes, it may be impossible.

Brendan Smith
Brendan Smith
IT Security Expert
First, perform a PC scan using an antivirus tool!
I will assist you in removing the Cdcc virus and guide you through the process of decrypting or restoring encrypted files. Below, you will find several universally applicable methods to recover encrypted .cdcc files. It is crucial to thoroughly read and comprehend the entire set of instructions. Do not skip any steps. Each step is of utmost importance and must be completed by you.
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📌 Important Note!

It is essential to voice that paying off the bill does not guarantee the successful files recovery. The crooks behind the Cdcc virus are known for their untrustworthiness. There have been instances where victims have paid the ransom, only to be denied by the cyber criminals with the decryption key provision.

Cdcc employs a unique key for each victim, with one exception:

  • If Cdcc fails to establish a connection with its command and control server (C&C Server) before starting the encryption process, it uses offline keys as a fallback option. This key is the same for all users, allowing for the decryption of files encrypted by the ransomware.

The Cdcc virus is similar to other DJVU ransomware samples such as Cdxx, Lkhy, Cdpo, and Cdwe. This virus encrypts a wide range of common file types and appends its distinct “.cdcc” extension to all files. For instance, a file named “1.jpg” would be altered to “1.jpg.cdcc” and “2.png” to “2.png.cdcc“.

After successful encryption, the virus creates a special text file named “_readme.txt” and places it in every folder containing the encrypted files. It also adds this file to the desktop, so the user will not miss the attack even without opening folders.

The image below provides a visual representation of files with the “cdcc” extension:

Cdcc Virus - encrypted cdcc files

Encrypted Files by STOP/DJVU Ransomware

Name Cdcc Virus
Ransomware family1 DJVU/STOP2 ransomware
Extension .cdcc
Ransomware note _readme.txt
Ransom From $999 to $1999 (in Bitcoins)
Contact [email protected], [email protected]
Detection Backdoor:Win32/Xtrat.B Virus Removal, Ransom:Win32/Mazedec.TA!MSR Virus Removal, Picsys.Worm.Bot.DDS Virus Removal
  • Installs password-stealing Trojan on the system, like Vidar Stealer or RedLine Stealer;
  • Adds a list of domains to the HOSTS file to block access to certain security-related sites;
  • Encrypts most of your files (photos, videos, documents) and adds a particular “.cdcc” extension;
  • Manages to install a SmokeLoader backdoor;
  • Can delete Volume Shadow copies to make victim’s attempts to restore data impossible;
Fix Tool To remove possible malware infections, scan your PC:

6-day free trial available.

This message asking for payment is for restoring files via decryption key:

_readme.txt (STOP/DJVU Ransomware)

_readme.txt (STOP/DJVU Ransomware) – The alarming notification requesting users to pay the ransom to decrypt the encoded data contains these frustrating cautions.

Cdcc ransomware arrives as a set of operations that are meant to execute certain functions on a victim’s computer. One of the primary processes being launched is winupdate.exe, a deceptive process that displays a fraudulent Windows update alert during the attack. Such a trick helps to convince the victim that their PC has become slow because of a Windows update.

Meanwhile, the ransomware runs another process (named 4 random chars) which initiates scanning the computer for target files and ciphering them. Next, the ransomware deletes Volume Shadow Copies from the system through the following CMD command:

vssadmin.exe Delete Shadows /All /Quiet

Once deleted, it becomes virtually impossible to recover the previous computer state using System Restore Points. The issue is, that ransomware operators are getting rid of any built-in Windows methods that could assist the victim to regain files for free. In addition, the rascals modify the Windows HOSTS file by appending a list of domains to it and linking them to the localhost IP. As a result, the victim will face a DNS_PROBE_FINISHED_NXDOMAIN error when accessing one of the blocked websites.

It has come to our attention that ransomware endeavors to restrict websites that publish various how-to guides for computer users. It is obvious that by hindering specific domains, the malefactors are attempting to prevent the victim from accessing relevant and helpful ransomware-attack-related information online. The virus also saves two .txt files on the victim’s computer that provide attack-related particulars – the victim’s public key and personal ID. These two files are named bowsakkdestx.txt and PersonalID.txt.

Cdcc ransomware virus saves public encryption key and victim's id in bowsakkdestx.txt file

After all these alterations, the malware doesn’t cease. Variants of STOP/DJVU are inclined to release Vidar password-stealing Trojan on compromised systems. This threat carries an extensive list of capabilities, including:

  • Manipulating and viewing files on the victim’s computer without their knowledge.
  • Extracting sensitive information such as browser cookies, saved passwords, and browsing history.
  • Obtaining unauthorized access to login credentials of Steam, Telegram, and Skype.
  • Granting the hackers remote control over the victim’s computer for various malicious activities.
  • Stealing cryptocurrency wallets from the victim’s system.
  • Gathering sensitive data by running malicious software on the victim’s computer.

The encryption algorithm used by the DJVU/STOP virus is AES-256. So, once your data is encrypted with an online decryption key, the chances of getting your files back without paying the ransom are quite low. The thing is, this key is unique for each victim, and picking it will take too much time.

Obtaining the online decryption key in any other way is also close to impossible. It is stored on a server controlled by the criminals who spread the Cdcc malware. For receiving the decrypting code the payment should be $1999. To get the payment details, the victims should contact the hackers by email ([email protected]).

The message by the ransomware states the following information:


Don't worry, you can return all your files!
All your files like pictures, databases, documents, and other important are encrypted with the strongest encryption and unique key.
The only method of recovering files is to purchase a decrypt tool and a unique key for you.
This software will decrypt all your encrypted files.
What guarantees do you have?
You can send one of your encrypted files from your PC and we decrypt it for free.
But we can decrypt only 1 file for free. The file must not contain valuable information.
You can get and look video overview decrypt tool:
The price of private key and decrypt software is $1999.
A discount of 50% is available if you contact us first 72 hours, that's the price for you is $999.
Please note that you'll never restore your data without payment.
Check your e-mail "Spam" or "Junk" folder if you don't get an answer for more than 6 hours.

To get this software you need to write to our e-mail:
[email protected]

Reserve an e-mail address to contact us:
[email protected]

Your personal ID:

How To Remove STOP/Djvu Ransomware?

Remove Cdcc Virus with Gridinsoft Anti-Malware

We have also been using this software on our systems ever since, and it has always been successful in detecting viruses. It has blocked the most common Ransomware as shown from our tests with the software, and we assure you that it can remove Cdcc Virus as well as other malware hiding on your computer.

Gridinsoft Anti-Malware - Main Screen

To use Gridinsoft for remove malicious threats, follow the steps below:

1. Begin by downloading Gridinsoft Anti-Malware, accessible via the blue button below or directly from the official website

2.Once the Gridinsoft setup file (setup-gridinsoft-fix.exe) is downloaded, execute it by clicking on the file.


3.Follow the installation setup wizard's instructions diligently.

Gridinsoft Setup Wizard

4. Access the "Scan Tab" on the application's start screen and launch a comprehensive "Full Scan" to examine your entire computer. This inclusive scan encompasses the memory, startup items, the registry, services, drivers, and all files, ensuring that it detects malware hidden in all possible locations.

Scan for Cdcc Virus Ransomware

Be patient, as the scan duration depends on the number of files and your computer's hardware capabilities. Use this time to relax or attend to other tasks.

5. Upon completion, Anti-Malware will present a detailed report containing all the detected malicious items and threats on your PC.

The Cdcc Virus was Found

6. Select all the identified items from the report and confidently click the "Clean Now" button. This action will safely remove the malicious files from your computer, transferring them to the secure quarantine zone of the anti-malware program to prevent any further harmful actions.

The Cdcc Virus has been removed

8. If prompted, restart your computer to finalize the full system scan procedure. This step is crucial to ensure thorough removal of any remaining threats. After the restart, Gridinsoft Anti-Malware will open and display a message confirming the completion of the scan.

Remember Gridinsoft offers a 6-day free trial. This means you can take advantage of the trial period at no cost to experience the full benefits of the software and prevent any future malware infections on your system. Embrace this opportunity to fortify your computer's security without any financial commitment.

Trojan Killer for “Cdcc Virus” removal on locked PC

In situations where it becomes impossible to download antivirus applications directly onto the infected computer due to malware blocking access to websites, an alternative solution is to utilize the Trojan Killer application.

Trojan Killer - Main View

There is a really little number of security tools that are able to be set up on the USB drives, and antiviruses that can do so in most cases require to obtain quite an expensive license. For this instance, I can recommend you to use another solution of GridinSoft - Trojan Killer Portable. It has a 14-days cost-free trial mode that offers the entire features of the paid version. This term will definitely be 100% enough to wipe malware out.

Trojan Killer is a valuable tool in your cybersecurity arsenal, helping you to effectively remove malware from infected computers. Now, we will walk you through the process of using Trojan Killer from a USB flash drive to scan and remove malware on an infected PC. Remember, always obtain permission to scan and remove malware from a computer that you do not own.

Step 1: Download & Install Trojan Killer on a Clean Computer:

1. Go to the official GridinSoft website ( and download Trojan Killer to a computer that is not infected.

Download Trojan Killer

2. Insert a USB flash drive into this computer.

3. Install Trojan Killer to the "removable drive" following the on-screen instructions.

Install Trojan Killer to Removable Drive

4. Once the installation is complete, launch Trojan Killer.

Step 2: Update Signature Databases:

5. After launching Trojan Killer, ensure that your computer is connected to the Internet.

6. Click "Update" icon to download the latest signature databases, which will ensure the tool can detect the most recent threats.

Click Update Button

Step 3: Scan the Infected PC:

7. Safely eject the USB flash drive from the clean computer.

8. Boot the infected computer to the Safe Mode.

9. Insert the USB flash drive.

10. Run tk.exe

11. Once the program is open, click on "Full Scan" to begin the malware scanning process.

Searching Cdcc Virus Virus

Step 4: Remove Found Threats:

12. After the scan is complete, Trojan Killer will display a list of detected threats.

Searching Cdcc Virus Finished

13. Click on "Cure PC!" to remove the identified malware from the infected PC.

14. Follow any additional on-screen prompts to complete the removal process.

Restart needed

Step 5: Restart Your Computer:

15. Once the threats are removed, click on "Restart PC" to reboot your computer.

16. Remove the USB flash drive from the infected computer.

Congratulations on effectively removing Cdcc Virus and the concealed threats from your computer! You can now have peace of mind, knowing that they won't resurface again. Thanks to Gridinsoft's capabilities and commitment to cybersecurity, your system is now protected.

Video Guide

How To Decrypt .cdcc Files?

How to restore big files?

Try removing .cdcc extension on a few big files and opening them. This malware has issues with large file encryption. Either the virus scanned and did not lock the file, or it bugged and did not add the filemarker. If your files are very large (2GB+), such a situation is highly probable. Please, text me in the comments whether this helped you or not.

The newest extensions were released around the end of August 2019 after the criminals made changes. This includes Cdxx, Cdtt, Cdpo etc.

As a consequence of the modifications made by the criminals, STOPDecrypter is no longer assisted. It has been replaced with the Emsisoft Decryptor for STOP Djvu Ransomware developed by Emsisoft.

You can download free decryption tool here: Decryptor for STOP Djvu.

  1. Download and run the decryption tool.

    Start downloading the decryption tool.

    Make sure to launch the decryption utility as an administrator. You need to agree with the license terms that will come up. For this purpose, click on the “Yes” button:

    Emsisoft Decryptor - license terms

    As soon as you accept the license terms, the main decryptor user interface comes up:

    Emsisoft Decryptor - user interface

  2. Select folders for decryption.

    Based on the default configurations, the decryptor will by default choose the reachable directories to decode the currently reachable drives (the connected ones), including the network drives. You can select other locations with the “Add” button.

    Decryptors usually propose several options considering the specific malware family. The possible options are presented in the Options tab and can be turned on or turned off there. You may find a detailed list of the currently active Options below.

  3. Click on the “Decrypt” button.

    As soon as you add all the desired locations for decryption to the list, click on the “Decrypt” button to initiate the decryption procedure.

    Note that the main screen may turn you to a status view, letting you know of the active process and the decryption statistics of your data:

    Emsisoft Decryptor - the decryption statistics

    The decryptor will notify you once the decryption procedure is completed. If you need the report for your papers, you can save it by choosing the “Save log” button. Note that it is also possible to copy it directly to your clipboard and paste it into emails or messages here if you need to do so.

The Emsisoft Decryptor might display different messages after a failed attempt to restore your files:

✓ Error: Unable to decrypt a file with ID: [your ID]

There is no corresponding decryption key in the Emsisoft decryptor’s database.

✓ No key for New Variant online ID: [your ID]

Notice: this ID appears to be an online ID, decryption is impossible

Your original files were encrypted with an online key. There is no one to share the decryption key with you. File recovery is only possible through paying the ransom. 🙁

✓ Result: No key for new variant offline ID: [example ID]

This ID appears to be an offline ID. Decryption may be possible in the future.

An offline key was used, though the file recovery operation failed (the offline decryption key isn’t available yet). Nonetheless, this message is good news for you, since it is possible to restore your files in the future. 🙂

It can take a few weeks or months until the decryption key gets found and uploaded to the decryptor. Please follow updates regarding the decryptable DJVU versions here.

✓ Remote name could not be resolved

This stands for a DNS issue. Try resetting your HOSTS file to default.

How to Restore .cdcc Files?

In some cases ransomware is not doom for your files…

The Cdcc ransomware encryption mechanism is next: it ciphers every file byte-by-byte, then saves a duplicate, erasing (not overriding!) the original file. Hence, the data of the file location on the disk drive is lost, but the original file is not removed from the physical disk. The cell, or the sector where this file was stored, can still hold this file, but it is not present in the file system and can be replaced by data that has been loaded to this drive after the deletion. Hence, it is possible to retrieve your files using special software.

I recently had my PC infected by this virus. It managed to bypass 2 Antivirus software and 2 malware fighters.

Anyway, after realizing it was an online algorithm, it was impossible to retrieve my encrypted files. I also had my backup drive plugged in at the time of the virus, and this was also infected, or so I thought. Every folder within my backup drive had been infected and was encrypted. However, despite losing some important files, I retrieved almost 80% of my 2TB storage.

When I started going through the folders, I noticed the readme.txt ransom note in every folder. I opened some of the folders and found that all files that were not in a subfolder within that folder had been encrypted. However, I found a flaw and a glimmer of hope when I went into the subfolders in other folders and found that these files had not been encrypted. Every folder within my c and d drives, including subfolders, had been encrypted, but this was not the case with the backup drive. Having subfolders created within a folder has saved 80% of my data.

As I said, I believe this to be only a small loophole on a backup drive. I’ve since found a further 10 % of my data on another hard drive on a different PC. So my advice is if you use a backup drive, create subfolders. I was lucky, I guess. But I was also unlucky that the virus hit as I was transferring some files from my backup.

Hopefully, this can help some other people in my situation.

Jamie Newland
Some pointers for recovery repair of Cdcc files (true for all STOP/DJVU variants):

  • I have seen Stop/Djvu variants fail to encrypt deeper nested folders, so that you can check that. You may find those are not encrypted.
  • This ransomware saves encrypted data to a new file and deletes the original. So there’s a slight chance part of that deleted file can be recovered using file recovery software. It’s unlikely the folder structure can be restored, so a free tool like PhotoRec may be as good as any.
  • This ransomware only partially encrypts (about the first 150 KB), so depending on file size and type of data, the non-encrypted part may be recoverable.
  • Joep

    Recovering your files with PhotoRec

    PhotoRec is a free open-source program, which is initially created for file recovery from damaged disks, or data recovery in case they are unintentionally deleted. However, as time has gone by, this program adopted the ability to recover the files of 400 different file types. Hence, it can be used for data recovery after the Cdcc attack.

    First, you need to download this app. It is 100% free, but the developer notifies you that there is no assurance that your files will be retrieved. PhotoRec is distributed together with other programs of the same developer – TestDisk. The program archive will bear the TestDisk name but don’t worry. PhotoRec files are right inside.

    To launch PhotoRec, you need to find and open “qphotorec_win.exe” file. No installation is needed – the program has all the files it needs inside of the archive, hence, you can fit it on your USB drive, and try to help your friends/parents/anyone who has been attacked by Cdcc ransomware.

    PhotoRec file in the folder for restore Cdcc files

    After the launch, you will see the screen showing you the entire list of your disk drives. However, these details are likely irrelevant, because the required menu is placed a bit higher. Click this bar, then choose the disk which was attacked by ransomware.

    Choose the disc in PhotoRec

    After picking the disk, you need to choose the destination folder for the recovered files. This menu is located at the lower part of the PhotoRec window. The best selection is to export them on a USB drive or any other type of removable disk.

    Choosing the destination folder of recovery Cdcc files

    Then, you need to designate the file formats. This setting is located at the bottom, too. As it was mentioned, PhotoRec can regain the files in about 400 different formats.

    Choose the file format

    Finally, you can begin file retrieval by pressing the “Search” button. You will view the screen where the outcomes of the scan and recovery are shown.

    Recovery process

    Frequently Asked Questions

    🤔 How can I open “.cdcc” files?

    No way. These files are encrypted by ransomware. The contents of encrypted files are not available until they are decrypted.

    🤔 This virus has blocked the infected PC: I can’t get the activation code.

    In this situation, you need to prepare the memory stick with a pre-installed Trojan Killer.

    🤔 Decryptor did not decrypt all my files, or not all of them were decrypted. What should I do?

    Have patience. You are infected with the new version of STOP/DJVU ransomware, and decryption keys have not yet been released. Follow the news on our website.

    We will keep you posted when new keys or new decryption programs appear.

    🤔 What can I do right now?

    The Cdcc ransomware encrypts only the first 150KB of files. So MP3 files are rather large, some media players (Winamp for example) may be able to play the files, but – the first 3-5 seconds (the encrypted portion) will be missing.

    You can try to find a copy of an original file that was encrypted:

    • Files you downloaded from the Internet that were encrypted and you can download again to get the original.
    • Pictures that you shared with family and friends that they can just send back to you.
    • Photos that you uploaded on social media or cloud services like Carbonite, OneDrive, iDrive, Google Drive, etc
    • Attachments in emails you sent or received and saved.
    • Files on an older computer, flash drive, external drive, camera memory card, or iPhone where you transferred data to the infected computer.

    If the guide doesn’t help you to remove the infection, please download the GridinSoft Anti-Malware that I recommended. Do not forget to share your experience in solving the problem. Please leave a comment here! This can help other victims to understand they are not alone. And together we will find ways to deal with this issue.

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    Brendan Smith
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    1. My files are encrypted by ransomware, what should I do now?
    2. About DJVU (STOP) Ransomware.

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    About the author

    Brendan Smith

    I'm Brendan Smith, a passionate journalist, researcher, and web content developer. With a keen interest in computer technology and security, I specialize in delivering high-quality content that educates and empowers readers in navigating the digital landscape.

    With a focus on computer technology and security, I am committed to sharing my knowledge and insights to help individuals and organizations protect themselves in the digital age. My expertise in cybersecurity principles, data privacy, and best practices allows me to provide practical tips and advice that readers can implement to enhance their online security.

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