The Return of CryptoLocker Ransomware - How to, Technology and PC Security Forum |

The Return of CryptoLocker Ransomware

Created in 2013, CryptoLocker is a ransomware that targets all Windows versions. Through asymmetric encryption, certain files available on the user’s PC are encrypted, and a ransom message is displayed. The sum requested for the decryption of the files is between $100 and $300 and it comes with a timer that threatens to delete the encryption key in case the money is not paid in the next 72 hours via Bitcoins or MoneyPak vouchers.

Download a System Scanner, to See If Your System Has Been Affected By CryptoLocker.

How Does CryptoLocker Infect the User’s PC?

CryptoLocker enters the user’s PC through an email attachment. The corrupted file is disguised as an email message concerning account charge alert, missing package delivery, or other customer support issues from a popular company.

The file has a .zip attachment and by opening it, the user lets the ransomware in and infects the computer. The .zip files are offered in the form of normal PDF files, which can easily mislead the user.


The Encryption of the CryptoLocker

CryptoLocker is usually distributed via an attachment, which is downloaded by the user. Then it saves itself on the PC to the root of the %AppData% or %LocalAppData% folder path, where the program settings are stored, along with temporary files created by applications. CryptoLocker creates a file in the registry, which is automatically launched as soon as the user logs in.

Then the CryptoLocker deceits all the files with an .EXE extension on the user’s computer and thus next time the executable is launched the program attempts to delete the Shadow Volume Copies on the victim’s PC, so that it wouldn’t be able to restore the files that are encrypted. Once the Shadow Volume Copies are deleted, the .EXE are being restored to the Windows defaults.

CryptoLocker uses asymmetric encryption. This means that it requires a public and private key. It finds the Command & Control server to get the public key for the encryption of files that are encrypted. CryptoLocker ransomware can encrypt files with the following extensions: *.odt, *.ods, *.odp, *.odm, *.odc, *.odb, *.doc, *.docx, *.docm, *.wps, *.xls, *.xlsx, *.xlsm, *.xlsb, *.xlk, *.ppt, *.pptx, *.pptm, *.mdb, *.accdb, *.pst, *.dwg, *.dxf, *.dxg, *.wpd, *.rtf, *.wb2, *.mdf, *.dbf, *.psd, *.pdd, *.pdf, *.eps, *.ai, *.indd, *.cdr, *.jpg, *.jpe, *.jpg, *.dng, *.3fr, *.arw, *.srf, *.sr2, *.bay, *.crw, *.cr2, *.dcr, *.kdc, *.erf, *.mef, *.mrw, *.nef, *.nrw, *.orf, *.raf, *.raw, *.rwl, *.rw2, *.r3d, *.ptx, *.pef, *.srw, *.x3f, *.der, *.cer, *.crt, *.pem, *.pfx, *.p12, *.p7b, *.p7c.

Once the files are encrypted, the PC user receives a ransom message on the screen. In case the user does not transfer the required payment, the encryption key stored on the C&C server is destroyed between 24 and 72 hours from receiving the message.

The cyber criminals claim that the code for the encryption is generated on the infected computer itself, which means that if the decryption key is deleted, then the data cannot be restored. In the last versions of CryptoLocker, the cyber criminals present an option for uploading the infected file to a website, provided by CryptoLocker, offering an attempt to decrypt it. The result might be reported to the user within 24 hours after the upload, but then the decryption price is raised to 10 BTC.

How to React If Your Computer Is Infected with CryptoLocker?

Users who find out that their PC is infected with CryptoLocker should immediately disconnect it from the Internet in order to stop further encryption. Many of the users who have paid the ransom inform that a new message appears on the screen confirming that the verification process has been started. This process goes on for up to 3-4 hours. When it is completed, an automatic decryption of the files starts. In some cases, a message appears that certain files cannot be decrypted.

Preventing a CryptoLocker Infection

In order to prevent CryptoLocker Infection on their computers, the users should:

  • Use a password protection in case of file-sharing
  • Remove services and programs that are not needed
  • Block or remove email attachments that distribute infections
  • Use a firewall for incoming connections
  • Disable the automatic launching of .exe files

The Return of CryptoLocker

During a massive operation called “Operation Tovar” led by the FBI, the US Department of Justice, Europol and the NCA, at the beginning of June 2014, the communication between Gameover Zeus and its C&C servers has been disconnected. Through a combination of Gameover Zeus and CryptoLocker botnets, the cyber criminals were targeting users all over the world, affecting around 500,000 computers before the successful operation.

The cyber criminals were using Gameover Zeus to infect the computers of the users with CryptoLocker and then display the ransom message to the victims. New versions of the ransomware appeared shortly after that with an improved code. Among them are New CryptoLocker, CryptoDefense, CryptoWall, DirCrypt. They are expected to create new networks of infected computers. In some of the new versions, the user gets instructions for the payment in text-files in the encrypted folders, while in others the payment is requested through TOR anonymity network which hides and protects the cyber criminals’ identity.

Remove CryptoLocker automatically with Spy Hunter Malware – Removal Tool.

You may want to clean your system with a powerful anti-malware solution. For future reference, always remember to back up important files so that ransomware consequences are decreased to the minimum. For that purpose, an external storage device may be used, as well as a cloud service.

Spy Hunter scanner will only detect the threat. If you want the threat to be automatically removed, you need to purchase the full version of the anti-malware tool.Find Out More About SpyHunter Anti-Malware Tool / How to Uninstall SpyHunter


Berta Bilbao

Berta is a dedicated malware researcher, dreaming for a more secure cyber space. Her fascination with IT security began a few years ago when a malware locked her out of her own computer.

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Windows Mac OS X

How to Remove CryptoLocker from Windows.

Step 1: Boot Your PC In Safe Mode to isolate and remove CryptoLocker


Manual Removal Usually Takes Time and You Risk Damaging Your Files If Not Careful!
We Recommend To Scan Your PC with SpyHunter

Keep in mind, that SpyHunter’s scanner is only for malware detection. If SpyHunter detects malware on your PC, you will need to purchase SpyHunter's malware removal tool to remove the malware threats. Read our SpyHunter 5 review. Click on the corresponding links to check SpyHunter's EULA, Privacy Policy and Threat Assessment Criteria

1. Hold Windows key() + R

2. The "Run" Window will appear. In it, type "msconfig" and click OK.

3. Go to the "Boot" tab. There select "Safe Boot" and then click "Apply" and "OK".
Tip: Make sure to reverse those changes by unticking Safe Boot after that, because your system will always boot in Safe Boot from now on.

4. When prompted, click on "Restart" to go into Safe Mode.

5. You can recognise Safe Mode by the words written on the corners of your screen.

Step 2: Uninstall CryptoLocker and related software from Windows

Here is a method in few easy steps that should be able to uninstall most programs. No matter if you are using Windows 10, 8, 7, Vista or XP, those steps will get the job done. Dragging the program or its folder to the recycle bin can be a very bad decision. If you do that, bits and pieces of the program are left behind, and that can lead to unstable work of your PC, errors with the file type associations and other unpleasant activities. The proper way to get a program off your computer is to Uninstall it. To do that:

1. Hold the Windows Logo Button and "R" on your keyboard. A Pop-up window will appear.

2. In the field type in "appwiz.cpl" and press ENTER.

3. This will open a window with all the programs installed on the PC. Select the program that you want to remove, and press "Uninstall"
Follow the instructions above and you will successfully uninstall most programs.

Step 3: Clean any registries, created by CryptoLocker on your computer.

The usually targeted registries of Windows machines are the following:

  • HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\Run
  • HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run
  • HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\RunOnce
  • HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\RunOnce

You can access them by opening the Windows registry editor and deleting any values, created by CryptoLocker there. This can happen by following the steps underneath:

1. Open the Run Window again, type "regedit" and click OK.

2. When you open it, you can freely navigate to the Run and RunOnce keys, whose locations are shown above.

3. You can remove the value of the virus by right-clicking on it and removing it.
Tip: To find a virus-created value, you can right-click on it and click "Modify" to see which file it is set to run. If this is the virus file location, remove the value.

Before starting "Step 4", please boot back into Normal mode, in case you are currently in Safe Mode.
This will enable you to install and use SpyHunter 5 successfully.

Step 4: Scan for CryptoLocker with SpyHunter Anti-Malware Tool

1. Click on the "Download" button to proceed to SpyHunter's download page.

It is recommended to run a scan before purchasing the full version of the software to make sure that the current version of the malware can be detected by SpyHunter. Click on the corresponding links to check SpyHunter's EULA, Privacy Policy and Threat Assessment Criteria.

2. After you have installed SpyHunter, wait for it to update automatically.


3. After the update process has finished, click on the 'Malware/PC Scan' tab. A new window will appear. Click on 'Start Scan'.


4. After SpyHunter has finished scanning your PC for any files of the associated threat and found them, you can try to get them removed automatically and permanently by clicking on the 'Next' button.


If any threats have been removed, it is highly recommended to restart your PC.

Step 5 (Optional): Try to Restore Files Encrypted by CryptoLocker.

Ransomware infections and CryptoLocker aim to encrypt your files using an encryption algorithm which may be very difficult to decrypt. This is why we have suggested a data recovery method that may help you go around direct decryption and try to restore your files. Bear in mind that this method may not be 100% effective but may also help you a little or a lot in different situations.

1. Download the reccomended Data Recovery software by clicking on the link underneath:

If the above link does not work for you and your region, try the other two links below, that lead to the same product:


2. On the download page, click on the "Download" button:

3. Click on "Save File" button:

4. Accept all agreements and click "Next":

5. After all the "Next" steps, click on "Install" and then wait for the installation to complete:

6. Run the software. Click on the location to scan for missing or deleted files and click on "Scan":

7. Wait for the scan to complete, it may take some time. Be advised that this scan is not 100% guaranteed to recover all files, but it does have some chance to get your data back:

Windows Mac OS X

Get rid of CryptoLocker from Mac OS X.

Step 1: Uninstall CryptoLocker and remove related files and objects

Manual Removal Usually Takes Time and You Risk Damaging Your Files If Not Careful!
We Recommend To Scan Your Mac with SpyHunter for Mac
Keep in mind, that SpyHunter for Mac needs to purchased to remove the malware threats. Click on the corresponding links to check SpyHunter’s EULA and Privacy Policy

1. Hit the ⇧+⌘+U keys to open Utilities. Another way is to click on “Go” and then click “Utilities”, like the image below shows:

2. Find Activity Monitor and double-click it:

3. In the Activity Monitor look for any suspicious processes, belonging or related to CryptoLocker:

Tip: To quit a process completely, choose the “Force Quit” option.

4. Click on the "Go" button again, but this time select Applications. Another way is with the ⇧+⌘+A buttons.

5. In the Applications menu, look for any suspicious app or an app with a name, similar or identical to CryptoLocker. If you find it, right-click on the app and select “Move to Trash”.

6: Select Accounts, after which click on the Login Items preference. Your Mac will then show you a list of items that start automatically when you log in. Look for any suspicious apps identical or similar to CryptoLocker. Check the app you want to stop from running automatically and then select on the Minus (“-“) icon to hide it.

7: Remove any left-over files that might be related to this threat manually by following the sub-steps below:

  • Go to Finder.
  • In the search bar type the name of the app that you want to remove.
  • Above the search bar change the two drop down menus to “System Files” and “Are Included” so that you can see all of the files associated with the application you want to remove. Bear in mind that some of the files may not be related to the app so be very careful which files you delete.
  • If all of the files are related, hold the ⌘+A buttons to select them and then drive them to “Trash”.

In case you cannot remove CryptoLocker via Step 1 above:

In case you cannot find the virus files and objects in your Applications or other places we have shown above, you can manually look for them in the Libraries of your Mac. But before doing this, please read the disclaimer below:

Disclaimer! If you are about to tamper with Library files on Mac, be sure to know the name of the virus file, because if you delete the wrong file, it may cause irreversible damage to your MacOS. Continue on your own responsibility!

1: Click on "Go" and Then "Go to Folder" as shown underneath:

2: Type in "/Library/LauchAgents/" and click Ok:

3: Delete all of the virus files that have similar or the same name as CryptoLocker. If you believe there is no such file, do not delete anything.

You can repeat the same procedure with the following other Library directories:

→ ~/Library/LaunchAgents

Tip: ~ is there on purpose, because it leads to more LaunchAgents.

Step 2: Scan for and remove CryptoLocker files from your Mac

When you are facing problems on your Mac as a result of unwanted scripts and programs such as CryptoLocker, the recommended way of eliminating the threat is by using an anti-malware program. Combo Cleaner offers advanced security features along with other modules that will improve your Mac’s security and protect it in the future.

Step 3 (Optional): Try to Restore Files Encrypted by CryptoLocker on your Mac.

Ransomware for Mac CryptoLocker aims to encode all your files using an encryption algorithm which may be very difficult to decode, unless you pay money. This is why we have suggested a data recovery method that may help you go around direct decryption and try to restore your files, but only in some cases. Bear in mind that this method may not be 100% effective but may also help you a little or a lot in different situations.

1. Download the recommended Data Recovery Mac app by clicking on the link underneath:

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