How to remove RexCrypt Ransomware

RexCrypt ransomware is a dangerous computer virus. It targets computer files such as documents, presentations, spreadsheets, drawings, archives, databases, photos, images, and other common user’s data. Like most ransomware, RexCrypt virus is aiming to extort money from computer users by denying them access to files. In order to accomplish this task, RexCrypt ransowmare was designed to apply a highly complex algorithm to encrypt the data and at the same time, it alters the format by appending strings of characters as id=12345678.email=Legacy1@tutamail.com.RexCrypt. As a result, the common file abc.doc will turn into abc.doc.id=12345678.email=Legacy1@tutamail.com.RexCrypt.

How RexCrypt Infects the Computer?

Attackers are employing different campaigns to deploy RexCrypt ransomware. It can arrive on the computer via spam email messages, drive-by-download techniques, cracked programs, malicious freeware, social engineering attacks, Trojan Dropper, and dubious advertisements. Below are the details.

Spam email messages masking from a valid organization may arrive in the inbox with RexCrypt ransomware as an attached file. Of course, the virus is under the guise of valid documents so the recipient will not be suspicious. Upon opening the attached file, RexCrypt virus initiates the infection without a notice.

Drive-by-download techniques or also known as web injectors are infected websites that hackers are using to infect the visitors computer with RexCrypt ransomware. Malicious scripts on the said website automatically download the virus by exploiting certain vulnerabilities in internet program.

Cracked Software that computer users are downloading from different sources may have RexCrypt ransomware. Aside from unlawful, installing these maliciously modified applications can be the source of virus infection. The same thing goes with dubious freeware that several questionable websites are offering as free download.

Social engineering attacks can easily trick user because the file or malicious links were sent from a legitimate contacts. The receiver who often falls into this trick are not aware that the account of the other party is hacked or mimicked by attackers.

Trojan Dropper is a minor virus that is able to conceal themselves from security applications. Once inside the computer, it communicates with a remote server to download a copy of RexCrypt ransomware. It basically serves as advanced party and because its obscure the presence, it can freely perform various malicious actions on the infected computer.

RexCrypt Encryption / Decryption

The moment that RexCrypt ransomware is active on the system, it sends a report to command-and-control (C&C) server. Then, the server sends back command to initiate the encryption process and at the same time, it provides a public key for this specific infected computer. RexCrypt ransomware will proceed with the file-locking actions using a sophisticated algorithm. This will make it impossible for users to access or open the infected files.

Image of RexCrypt infected files

Ransom note file called How-To-Decrypt-My-Files.hta is generated as notice about the current infection. It also contains instructions to retrieve RexCrypt decryption tool that is in the possession of attackers. As what goes with majority of ransomware attack, makers of RexCrypt demands money are payment for the recovery program and private key that are needed to accomplish a successful file decryption.

Technical Details
Threat NameRexCrypt Ransomware, Hunt
Threat TypeCrypto-virus, File Locker, Encryption Virus
File Extension.id=(unique id).email=Legacy1@tutamail.com.RexCrypt
Ransomware Note FileHow-To-Decrypt-My-Files.hta
Attacker’s emailLegacy1@tutamail.com
Discovered by@demonslay335

Backup your files

One important step before proceeding with the procedures below is to backup your files. Ransomware are not the same. Each has its unique sets of payloads aside from encrypting the files with complex method. Others tend to delete the infected files after certain period, while others keep them concealed on hidden places. In addition, ransomware decryption tools are not guaranteed to be perfect, there are instances that files suffer from damages during the decryption process.

So, create a backup copy of your entire RexCrypt encrypted files right now.

RexCrypt Ransomware Removal Guide

First thing to do is remove the RexCrypt virus before attempting the decryption. Remember that as long as the ransomware is active, it will repeatedly encrypt the files on the compromised computer.

Infection of RexCrypt ransom virus is dangerous to the system because it can inject files that runs each time Windows starts. To prevent the malicious files from loading, Windows operating system must run with minimal process and it can be done through SafeMode With Networking.

Stage 1 : Temporarily Disable System Restore on Windows OS

Because RexCrypt and relevant virus is capable of reinstating itself by exploiting the System Restore of Windows, we suggests that you temporary disable System Restore while executing the steps. This option is also helpful to effectively run a full scan on the computer.

Do not forget to enable back System Restore after completing the removal of RexCrypt ransomware. This feature is vital in reinstating the operating system to previous normal working condition in case of problems or conflicts occurs.

Stage 2 : Start Windows in Safe Mode With Networking

Windows 10 Guide

1. Click on Windows logo and select Power icon when options pop-ups.
2. Select Restart from the options while pressing Shift key on the keyboard.
3. Choose an Option window will appear, select the Troubleshoot button.
4. On next window, please choose Advanced Option.
5. On Advanced Option window, click on Startup Settings and then, click Restart button to reboot the computer.
6. When Windows boot on Startup Settings, press function key F5 or number 5 on keyboard.

A simpler alternative for Windows 10 users is to scan the computer with Microsoft Defender Offline. This will run a virus scan in the recovery environment.

Windows 8 Guide

1. Click Windows Start icon at the lower left section of the screen.
2. Open Search window and type Advanced in the field. It will open General PC Settings.
3. Click on Advanced Startup and then, click on Restart Now button.
4. Once the computer starts in Advanced Startup option menu, select Troubleshoot.
5. Next, click on Advanced Options to reveal the next section.
6. Click Startup settings and then, click Restart button to boot the PC in Startup Settings.
7. Use function key F5 or number key 5 to Enable Safe Mode with Networking.

Stage 3 : Scan the Computer with Anti-Malware Tool

Ransomware files are placed deeply into the system and on various locations, thus, thorough scanning is vital to totally remove RexCrypt virus. Aside from our suggested tool, you may also run your own security program.

To remove RexCrypt automatically, scanning the computer with this efficient anti-malware tool is suggested. This scanner does not just uncover known threats like viruses or malware, it is also effective in discovering hazardous ransomware like RexCrypt.

1. Download free anti-malware scanner called MalwareBytes Anti-Malware.

2. After downloading, install the program. It may run automatically or you have to double-click on the downloaded file MBSetup.exe.

3. Carry out the installation with default setup process.

4. After the installation process, click the Get Started button to launch the program.

5. Continue with the prompts until the main program opens.

6. On the main console, click on Scan to run most complete detection method to find hidden objects associated to RexCrypt ransomware.

7. Scanning may take a while. Please wait until the anti-malware tool is done with the checking.

MBAM Scan

8. Once the scan has completed, the tool will display the list of detected threats. Remove all identified malicious items and restart the computer if necessary.

Stage 4 : Double-check with Microsoft's Malicious Software Removal Tool

1. Download the free scanner called Malicious Software Removal Tool.

Download MSRT

2. The tool automatically checks the operating system and suggest appropriate download version. Click on Download button to begin. Save the file to a convenient location, preferably on Desktop.

3. After downloading the file, Windows will prompt that download has completed. Click Run to start scanning for RexCrypt ransomware. Another option is to browse the location folder and double click on the file to run.

MSRT Icon

4. The tool will display Welcome screen, click Next. Please note the message "This tool is not a replacement for an antivirus product." You must understand that this program is made specifically to find and remove malware, viruses, Trojans, and other harmful elements on the computer. It was not designed to protect the computer.

MSRT Welcome

5. Next, you will see Scan Type. Please choose Full Scan to ensure that all RexCrypt ransom virus entities and other harmful files left on the computer will be found and removed. For advanced computer user, you can opt for Customized Scan, if there are other drives or folders you wanted to include in this scan.

MSRT Scan

6. Full scan may take a while, please wait for Malicious Software Removal Tool to complete the tasks. However, you may cancel the scan anytime by clicking on the Cancel button.

MSRT Scan

7. After scanning, the tool will reveal all identified threats. There may be other threats that our first scan fails to detect. Please remove/delete all detected items.

8. When removal procedure is complete, you may now close Malicious Software Removal Tool. We hope that RexCrypt ransomware have been completely deleted from the computer. Please restart Windows to proceed with the normal operation.

Recover Files from RexCrypt Ransomware Infection

On this section, we will provide ways to decrypt files infected with RexCrypt ransomware. Aside from dedicated decryption software and common tools, other options for file recovery are provided. As much as we can, we will update this area whenever there is new and more suitable decryption tool was made available.

Decrypting RexCrypt infected files with Emsisoft Tools

This service from Emsisoft is helpful in unlocking encrypted files without paying the ransom. It gives three ways to detect the ransomware and provide suitable recovery method:

Upload ransom note – This is usually the .txt or .hta files that was generated by RexCrypt ransomware.

Upload the encrypted file – The actual encrypted file. Choose the one that is less than 8MB in size.

Contact information – Enter the email address or any links provided as it appears in the ransom note of RexCrypt virus.

Emsisoft Tools

After submitting any of the appropriate data, Emsisoft will attempt to identify the ransomware and provide keys if there are available.

Option 1: Windows Previous Version Tool

Windows Vista and Windows 7 have a feature called Previous Versions. However, this tool is only usable if restore point was made prior to ransomware infection. To use this tool as "recovery option" for files encypted by RexCrypt virus, please follow these steps:

1. Open My Computer or Windows Explorer.

2. Right-click on the affected files or folders. From the drop-down list, please click on Restore previous versions.

3. New window will open display all backup copy of files and folders you wanted to recover. Choose the appropriate file and click on Open, Copy, or Restore. Restoring selected files overwrites the current locked files on the computer. The tool is not actually recovering files encrypted by RexCrypt. Instead, it restores files from backup copy.

Option 2: Use ShadowExplorer to restore files encrypted by RexCrypt Ransomware

Just like Previous Version tool, ShadowExplorer is taking advantage of shadow copy created by Windows. This tool allows you to retrieve older version of files before it was encrypted by RexCrypt ransomware.

1. Download ShadowExplorer from the official web site.

2. Install the program with the default settings.

3. The program should run automatically after installation. If not, double-click on ShadowExplorer icon.

4. You can see the drop-down list on top of the console. Please select proper drive and the most recent point-in-time shadow copies of files you wish to restore prior to RexCrypt ransomware infection.

shadow3

5. Right-click on the Drive, Folder, or File you wish to restore and click Export...

6. Lastly, ShadowExplorer will prompt for location where you want to save the copy of recovered files.

How to protect the computer from RexCrypt ransomware?

After the removal of the ransomware, it is important to prevent similar incident from happening again. In order to protect the computer effectively, computer user must know how RexCrypt ransomware was able to infect the computer. To minimize the possible infection, staying away from the common sources of this virus is crucial.

How RexCrypt ransomware can infect your computer?

The method of infecting the computers was found to be similar as other common viruses. Though, ransomware like RexCrypt is seen to have efficient deployment via spam email messages, web injectors, malicious software installers, misleading online advertisements, and through another virus infection.

Once the virus is executed, it immediately infects the system. Then, RexCrypt ransomware communicates to remote server so that unique key can be generated for the specific computer. After acquiring the key, it starts to decrypt target files using a complex method that is almost unbreakable. On the last stage of the attack, RexCrypt ransomware demands for ransom money as payment for the decryption tool. To further understand the attack scheme, we have included an infographic below.

Infographic image of ransomware attack stages
You can print, download, or share the infographic by clicking the image.

Securing the computer against ransomware attack

Do a Regular File Back-up - Always backup your data on a separate storage devices such as external hard drives, optical discs, or online backup services.

Keep Your Software Updated - Make sure that you have the latest software updates especially on the operating system. Recent updates often contain vital security patches to help protect the computer against all forms of threats.

Install a Security Program - Protect the computer with effective anti-virus application using efficient real-time scanning. Regularly run a complete scan to check the computer for presence of malware.

Protect your files with Controlled Folder Access (Windows 10)

For Windows 10 users, aside from protecting the computer using anti-virus or anti-malware programs, one way to protect against ransomware attack is by using Controlled Folder Access. This feature of Windows Defender Security Center may not prevent the RexCrypt ransomware infection, but it can protect the folder and files in general. Follow the steps to enable Controlled Folder Access in Windows 10.

1. Go to Windows 10 Taskbar and search for Windows Defender Security Center.

2. Open Windows Defender Security Center and click on Virus & Threat Protection icon.

Virus and Threat Protection

3. On next window, please click on Ransomware Protection.

4. Under Controlled Folder Access section, switch the slider to On. That will enable the feature and protect the folder against RexCrypt or any type of ransomware.

Controlled Folder Access

5. Click on Protected Folderslink to include additional folders. Make sure that folders where important files are located should be included in the list.

Add Protected Folder

Troubleshooting Guide

Certain programs maybe blocked by Controlled Folder Access feature. To fix the issue, simply have the specific program to be white listed.

1. Under Protected Folders, click Allow an app through controlled folder access.

2. Next, click the Add an allowed app and include the target executable file.

This Controlled Folder Access feature is one way to protect files against RexCrypt. Other important things to do in keeping files safe against ransomware is through early prevention like keeping programs updated, install an efficient security program, an do regular file backup on a separate media drive.

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