Hrosas Ransomware - How to remove

Hrosas is a virus — ransomware, a virus that affects Windows users. It tries to get money from people by breaking their files and threatening that the only way to get them back is to pay money to the extortionists who created the virus.

If you’re a victim of Hrosas, your files have been locked and had “.hrosas” appended to their name. The ransomware also creates a ransom note, the text of which is almost identical to the text of other DJVU type ransom notes. In it, the extortionists ask for $490 for decrypting your files and to contact them through [email protected] or [email protected].

What happened to your files?

The files are locked. They cannot be opened as they are now. Every popular type of file — video and audio recordings, music and movies, text documents and spreadsheets, archives and PDFs, all the other common file types. All victims of Hrosas are likely to have lost some important files.

The files have been encrypted. This means that they were put through an algorithm that scrambled their contents according to some specific encryption key. This can be reversed — but only if the decryption key is known. The problem is, only the extortionists have the decryption key.

Can the files be fixed?

The good news is, there is a decryptor for some DJVU type ransomware encrypted files. Here is a direct download link: STOPDecrypter v2.1.0.0.

Unfortunately, it only works for some Hrosas files that were encrypted with an offline key. Still, try the decryptor (and thank @demonslay335). It is possible that it will be improved in the future to decrypt more files, so if it doesn’t work for you now, you can save the files (and save the ransom note as it has your ID in it) and follow the development of STOPDecrypter, download an updated version, and try it again later.

You can also try to get some of your files back by using system restore — there is a guide below this article.

What do the creators of Hrosas want?

The developers of Hrosas wish to make money by extorting from those who cannot afford to lose their files. Indeed, businesses and some people have been paying the ransoms — hundreds of dollars for a person, thousands for a business. When it comes to ransomware, some of the people who pay the ransom do get their files back, but a lot of people don’t.

The creators of Hrosas want to rush people into paying the ransom money without them having the opportunity to collect their thoughts. This is why they have a “discount” for those who write to them in 72 hours from infection. Remember that you do not have to contact the cybercriminals and that they have no obligation to fulfill their promises — if you pay the money, be ready to be ignored, like a lot of people  who paid extortionists and did not get their files back.

Are the files you lost really irreplaceable? Maybe you have backups of the most important ones? It is a very good practice to keep a backup of your system, update it regularly, and store it separately from your computer, for example, in the cloud (Windows has tools to create these backups — take advantage of them). If you do have backups of your files, recovery from the Hrosas infection should not be very painful.

How to remove the Hrosas virus

First of all, back up any encrypted files that you want to try to decrypt later. Then scan your computer and remove the virus. Have a professional and reputable antivirus program do it, for example, Spyhunter.

Try to restore your files by following the instructions below, but I don’t promise that it will work for everyone.

In the future be more careful. Spam email attachments and pirated files sometimes carry viruses. Don’t open or run these files before you have scanned them with an antivirus program. Keep your antivirus up-to-date so that it’s ready to catch the newest threats.

How to recover Hrosas Ransomware encrypted files and remove the virus

Step 1. Restore system into last known good state using system restore

1. Reboot your computer to Safe Mode with Command Prompt:

for Windows 7 / Vista/ XP

• Start → Shutdown → Restart → OK.
• Press F8 key repeatedly until Advanced Boot Options window appears.
• Choose Safe Mode with Command Prompt.

for Windows 8 / 10

• Press Power at Windows login screen. Then press and hold Shift key and click Restart.
• Choose Troubleshoot → Advanced Options → Startup Settings and click Restart.
• When it loads, select Enable Safe Mode with Command Prompt from the list of Startup Settings.

 

2.Restore System files and settings.

• When Command Prompt mode loads, enter cd restore and press Enter.
• Then enter rstrui.exe and press Enter again.
• Click “Next” in the windows that appeared.
• Select one of the Restore Points that are available before Hrosas Ransomware has infiltrated to your system and then click “Next”.
• To start System restore click “Yes”.

 

Step 2. Complete removal of Hrosas Ransomware

After restoring your system, it is recommended to scan your computer with an anti-malware program, like Spyhunter and remove all malicious files related to Hrosas Ransomware. You can check other tools here.  

Step 3. Restore Hrosas Ransomware affected files using Shadow Volume Copies

If you do not use System Restore option on your operating system, there is a chance to use shadow copy snapshots. They store copies of your files that point of time when the system restore snapshot was created. Usually Hrosas Ransomware tries to delete all possible Shadow Volume Copies, so this methods may not work on all computers. However, it may fail to do so. Shadow Volume Copies are only available with Windows XP Service Pack 2, Windows Vista, Windows 7, and Windows 8. There are two ways to retrieve your files via Shadow Volume Copy. You can do it using native Windows Previous Versions or via Shadow Explorer. a) Native Windows Previous Versions Right-click on an encrypted file and select Properties → Previous versions tab. Now you will see all available copies of that particular file and the time when it was stored in a Shadow Volume Copy. Choose the version of the file you want to retrieve and click Copy if you want to save it to some directory of your own, or Restore if you want to replace existing, encrypted file. If you want to see the content of file first, just click Open.

b) Shadow Explorer It is a program that can be found online for free. You can download either a full or a portable version of Shadow Explorer. Open the program. On the left top corner select the drive where the file you are looking for is a stored. You will see all folders on that drive. To retrieve a whole folder, right-click on it and select “Export”. Then choose where you want it to be stored.

Step 4. Use Data Recovery programs to recover Hrosas Ransomware encrypted files

There are several data recovery programs that might recover encrypted files as well. This does not work in all cases but you can try this:

• We suggest using another PC and connect the infected hard drive as slave. It is still possible to do this on infected PC though.
• Download a data recovery program.
• Install and scan for recently deleted files.

Note: In many cases it is impossible to restore data files affected by modern ransomware. Thus I recommend using decent cloud backup software as precaution. We recommend checking out Carbonite, BackBlaze, CrashPlan or Mozy Home.