What is Horros ransomware? And how does it implement its attack?
Horros ransomware is a new crypto-malware discovered by a security researcher named Leo. This ransomware was first noticed in early April 2018 when there were reports made by victims regarding their files being inaccessible and marked with the “.horros” extension. This new crypto-malware is created based on HiddenTear – an open source platform exploited by cyber crooks to create ransomware infections. It is also created using the Visual Studio 2017 and does not leave any ransom note unlike most ransomware threats so aside from the files marked with the .horros extension, there are no other indications of its attack.
The main goal of Horros ransomware is to lock its victims’ important files so it can extort money from them via the Bitcoin crypto-currency. Horros ransomware implements its attack using a malicious executable file named “FileEncrypter.exe” which scans the system for specific file types to encrypt which according to researchers are the following file types:
.3dm, .3g2, .3gp, .7zip, .aaf, .accdb, .aep, .aepx, .aet, .ai, .aif, .as, .as3, .asf, .asp, .asx, .avi, .bmp, .c, .class, .cpp, .cs, .csv, .dat, .db, .dbf, .doc, .docb, .docm, .docx, .dot, .dotm, .dotx, .dwg, .dxf, .efx, .eps, .fla, .flv, .gif, .h, .idml, .iff, .indb, .indd, .indl, .indt, .inx, .jar, .java, .jpeg, .jpg, .js, .m3u, .m3u8, .m4u, .max, .mdb, .mid, .mkv, .mov, .mp3, .mp4, .mpa, .mpeg, .mpg, .msg, .pdb, .pdf, .php, .plb, .pmd, .png, .pot, .potm, .potx, .ppam, .ppj, .pps, .ppsm, .ppsx, .ppt, .pptm, .pptx, .prel, .prproj, .ps, .psd, .py, .ra, .rar, .raw, .rb, .rtf, .sdf, .sdf, .ses, .sldm, .sldx, .sql, .svg, .swf, .tif, .txt, .vcf, .vob, .wav, .wma, .wmv, .wpd, .wps, .xla, .xlam, .xll, .xlm, .xls, .xlsb, .xlsm, .xlsx, .xlt, .xltm, .xltx, .xlw, .xml, .xqx, .xqx, .zip
As mentioned, Horros ransomware does not leave any ransom note and the only outward indication that a computer is attacked is the files that are marked with the .horros extension. Horros ransomware uses the AES 256 encryption algorithm in encrypting files. Luckily, the encrypted files are decryptable as this ransomware is based on HiddenTear.
How does Horros ransomware proliferate?
Horros ransomware proliferates using either a malicious file attachment from spam email or via Remote Desktop Protocol services with unprotected configuration. In other words, it enters your system using a malicious file that you have obtained from a malicious spam email or the malicious file was installed itself by the attackers since Horros ransomware exploits RDP services.
Terminate Horros ransomware from your system by following the given removal guide below.
Step 1: Tap Ctrl + Shift + Esc keys to launch the Task Manager.
Step 2: Go to Processes and look for the malicious process of Horros ransomware named FileEncrypter.exe then right click on it and select End Process or End Task.
Step 3: Close the Task Manager and open Control Panel by pressing the Windows key + R, then type in appwiz.cpl and then click OK or press Enter.
Step 4: Look for dubious programs that might be related to Horros ransomware and then Uninstall it/them.
Step 5: Tap Win + E to launch File Explorer.
Step 6: After opening File Explorer, navigate to the following directories below and look for Horros ransomware’s malicious components such as the FileEncrypter.exe file and other suspicious-looking files and then remove them all.
Step 7: Close the File Explorer.
Before you proceed to the next steps below, make sure that you are tech savvy enough to the point where you know exactly how to use and navigate your computer’s Registry. Keep in mind that any changes you make will highly impact your computer. To save you the trouble and time, you can just use [product-name], this system tool is proven to be safe and excellent enough that hackers won’t be able to hack into it. But if you can manage Windows Registry well, then, by all means, go on to the next steps.
Step 8: Tap Win + R to open Run and then type in regedit in the field and tap enter to pull up Windows Registry.
Step 9: Navigate to the listed paths below and look for the registry keys and sub-keys created by Horros ransomware.
- HKEY_CURRENT_USER\Control Panel\Desktop\
- HKEY_USERS\.DEFAULT\Control Panel\Desktop\
Step 10: Delete the registry keys and sub-keys created by Horros ransomware.
Step 11: Close the Registry Editor.
Step 12: Empty your Recycle Bin.
Try to recover your encrypted files using the Shadow Volume copies
Restoring your encrypted files using Windows’ Previous Versions feature will only be effective if Horros ransomware hasn’t deleted the shadow copies of your files. But still, this is one of the best and free methods there is, so it’s definitely worth a shot.
To restore the encrypted file, right-click on it and select Properties, a new window will pop-up, then proceed to Previous Versions. It will load the file’s previous version before it was modified. After it loads, select any of the previous versions displayed on the list like the one in the illustration below. And then click the Restore button.
Once you’re done executing the steps given above, you need to continue the removal process of Horros ransomware using a reliable program like [product-name]. How? Follow the advanced removal steps below.
Perform a full system scan using [product-code]. To do so, follow these steps:
- Turn on your computer. If it’s already on, you have to reboot
- After that, the BIOS screen will be displayed, but if Windows pops up instead, reboot your computer and try again. Once you’re on the BIOS screen, repeat pressing F8, by doing so the Advanced Option shows up.
- To navigate the Advanced Option use the arrow keys and select Safe Mode with Networking then hit
- Windows will now load the SafeMode with Networking.
- Press and hold both R key and Windows key.
- If done correctly, the Windows Run Box will show up.
- Type in the URL address, [product-url] in the Run dialog box and then tap Enter or click OK.
- After that, it will download the program. Wait for the download to finish and then open the launcher to install the program.
- Once the installation process is completed, run [product-code] to perform a full system scan.