Guvara Ransomware

Also Known As: Guvara virus
Distribution: Moderate
Damage level: Severe

Guvara ransomware removal instructions

What is Guvara?

Guvara is a malicious program that belongs to the Djvu ransomware family. The person who discovered it is Michael Gillespie. As with most of ransomware, Guvara encrypts data and keeps it that way until a ransom is paid. Guvara renames every encrypted file by adding the ".guvara" extension, for example, if some file is named "1.jpg", then this ransomware changes its name to "1.jpg.guvara" and so on. It also puts a ransom note in every folder that contains encrypted files, it can be found by the name "_readme.txt".

As stated in the "_readme.txt" text file, victims can recover their files, however, to do so they must use a decryption tool that costs $980. It is possible to purchase it for a a lesser price ($490), but only if victims contact Guvara's developers in the first 72 hours after encryption. These cyber criminals also offer a free decryption of one file that does not contain any valuable information. They make this offer as a guarantee that they can be trusted and have a working decryption tool. To decrypt one file for free or to contact people who developed Guvara victims have to email them via merosa@india.com or merosa@firemail.cc. Cyber criminals make it cleat that the only way to recover files is to pay them the ransom and use their decryption tool. Unfortunately, that is true. Most ransomware-type programs encrypt data using cryptography algorithms (symmetric or asymmetric) that make decryptions without using particular tools impossible. Another problem is that cyber criminals cannot be trusted, once they get paid, they vanish. Simply said, victims get scammed. Typically, the only way to avoid data or/and financial loss is to restore files from a data backup.

Screenshot of a message encouraging users to pay a ransom to decrypt their compromised data:

Guvara decrypt instructions

Guvara is similar to other programs of this type such as MegaLocker, Langolier, Etols and many others. As a rule, cyber criminals use them to lock people's files and then to ask for a ransom. Most common differences between these viruses usually are the price of decryption/decryption tool and cryptography algorithm that was used to encrypt data. One way or another, most ransomware-type programs cause encryptions that cannot be decrypted without the help of cyber criminals who developed them. Unless a program is in a development state (is not finished) and has some bugs, flaws. To avoid such problem in the future, we recommend to create data backups regularly and store them on some remote server or unplugged storage device.

How did ransomware infect my computer?

Most common ways to spread various computer infections are through spam email campaigns, Trojans, unofficial/fake software updating tools, software 'cracking' tools and untrustworthy software download sources. Cyber criminals use spam campaigns to spread infections via malicious attachments that they include in their emails. Typically, these attachments are Microsoft Office documents, archives (ZIP, RAR and other files) PDFs, executables (.exe and others), JavaScript files and so on. If opened, these attachments download and install computer infections. Trojans are malicious programs that, if installed, cause chain infections. They are designed spread various viruses. Fake software updaters infect computers by downloading and installing malicious programs instead of fixes or updates, or by exploiting bugs, flaws of outdated installed programs. Third party tools that supposed to activate paid software for free often cause downloads and installations of malware. Free file hosting, freeware download websites, Per-to-Peer networks (like torrent clients, eMule etc.), third party software downloaders and other similar, unreliable software download sources can be used to spread viruses too. Cyber criminals present infected files (or rogue applications) as legitimate files. When downloaded and opened, they cause installations of various malicious programs.

Threat Summary:
Name Guvara virus
Threat Type Ransomware, Crypto Virus, Files locker
Encrypted Files Extension .guvara
Ransom Demanding Message _readme.txt text file
Ransom Amount $490/$980
Cyber Criminal Contact merosa@india.com, merosa@firemail.cc
Detection Names (807C.TMP.EXE) Avast (Win32:Trojan-gen), BitDefender (Trojan.GenericKD.41197210), ESET-NOD32 (a variant of Win32/Kryptik.GSAC), Kaspersky (Trojan-PSW.Win32.Coins.ret), Full List Of Detections (VirusTotal)
Symptoms Can't open files stored on your computer, previously functional files now have a different extension, for example my.docx.locked. A ransom demanding message is displayed on your desktop. Cyber criminals are asking to pay a ransom (usually in bitcoins) to unlock your files.
Additional Information Displays a fake Windows Update pop-up, modifies Windows Hosts file (to prevent users from accessing cyber security websites), injects AZORult trojan into the system.
Distribution methods Infected email attachments (macros), torrent websites, malicious ads.
Damage All files are encrypted and cannot be opened without paying a ransom. Additional password stealing trojans and malware infections can be installed together with a ransomware infection.
Removal

To eliminate Guvara virus our malware researchers recommend scanning your computer with Spyhunter.
▼ Download Spyhunter
Free scanner checks if your computer is infected. To remove malware, you have to purchase the full version of Spyhunter.

How to protect yourself from ransomware infections?

Files that are attached to emails received from unknown/suspicious addresses should not be trusted. If the email is irrelevant or suspicious, it is not recommended to open the included attachment (or click the presented web link). Download software from official websites and using direct links. All the sources that are mentioned above are not the safest tools do download any software. Update software using tools or implemented functions that are provided by official software developers only, and not some third party (fake, unofficial) updaters. Various software 'cracking' should not be used as well, besides, they are illegal. One more important thing is to have a reputable anti-virus or anti-spyware software installed and to keep it enabled at all times. If your computer is already infected with Guvara, we recommend running a scan with Spyhunter for Windows to automatically eliminate this ransomware.

Text presented in Guvara ransomware's text file "_readme.txt":

ATTENTION!

Don't worry my friend, you can return all your files!
All your files like photos, databases, documents and other important are encrypted
with strongest encryption and unique key.
The only method of recovering files is to purchase decrypt tool and unique key for you.
This software will decrypt all your encrypted files.
What guarantees you have?
You can send one of your encrypted file from your PC and we decrypt it for free.
But we can decrypt only 1 file for free. File must not contain valuable information.
You can get and look video overview decrypt tool:
hxxps://we.tl/t-1LFQOfI0Se
Price of private key and decrypt software is $980.
Discount 50% available if you contact us first 72 hours, that's price for you is $490.
Please note that you'll never restore your data without payment.
Check your e-mail "Spam" folder if you don't get answer more than 6 hours.

To get this software you need write on our e-mail:
merosa@india.com

Reserve e-mail address to contact us:
merosa@firemail.cc

Your personal ID:

-

Screenshot of files encrypted by Guvara (".guvara" extension):

Files encrypted by Guvara

As with most of ransomware from Djvu family, Guvara also displays a fake Windows update pop-up during the encryption:

Djvu ransomware family fake update

IMPORTANT NOTE! - Aside from encrypting data, ransomware-type infections from Djvu malware family also installs a trojan-type virus called AZORult, which is designed to steal various account credentials. Moreover, this malware family is designed to add a number of entries to the Windows hosts file. The entries contain URLs of various websites, most of which are related to malware removal. This is carried out with the intention of making users unable to access malware security websites and seek help. Our website (PCrisk.com) is also on the list. Removing these entries, however, is simple - you can find detailed instructions in this article (note that, although the steps are shown in the Windows 10 environment, the process is virtually identical on all versions of the Microsoft Windows operating system).

Screenshot of websites added to Windows hosts file:

Tro Ransomware adding websites to Windows Hosts file

Guvara ransomware removal:

Instant automatic removal of Guvara virus: Manual threat removal might be a lengthy and complicated process that requires advanced computer skills. Spyhunter is a professional automatic malware removal tool that is recommended to get rid of Guvara virus. Download it by clicking the button below:
▼ DOWNLOAD Spyhunter By downloading any software listed on this website you agree to our Privacy Policy and Terms of Use. Free scanner checks if your computer is infected. To remove malware, you have to purchase the full version of Spyhunter.

Quick menu:

Step 1

Windows XP and Windows 7 users: Start your computer in Safe Mode. Click Start, click Shut Down, click Restart, click OK. During your computer start process, press the F8 key on your keyboard multiple times until you see the Windows Advanced Option menu, and then select Safe Mode with Networking from the list.

Safe Mode with Networking

Video showing how to start Windows 7 in "Safe Mode with Networking":

Windows 8 users: Start Windows 8 is Safe Mode with Networking - Go to Windows 8 Start Screen, type Advanced, in the search results select Settings. Click Advanced startup options, in the opened "General PC Settings" window, select Advanced startup. Click the "Restart now" button. Your computer will now restart into the "Advanced Startup options menu". Click the "Troubleshoot" button, and then click the "Advanced options" button. In the advanced option screen, click "Startup settings". Click the "Restart" button. Your PC will restart into the Startup Settings screen. Press F5 to boot in Safe Mode with Networking.

Windows 8 Safe Mode with networking

Video showing how to start Windows 8 in "Safe Mode with Networking":

Windows 10 users: Click the Windows logo and select the Power icon. In the opened menu click "Restart" while holding "Shift" button on your keyboard. In the "choose an option" window click on the "Troubleshoot", next select "Advanced options". In the advanced options menu select "Startup Settings" and click on the "Restart" button. In the following window you should click the "F5" button on your keyboard. This will restart your operating system in safe mode with networking.

windows 10 safe mode with networking

Video showing how to start Windows 10 in "Safe Mode with Networking":

Step 2

Log in to the account infected with the Guvara virus. Start your Internet browser and download a legitimate anti-spyware program. Update the anti-spyware software and start a full system scan. Remove all entries detected.

If you cannot start your computer in Safe Mode with Networking, try performing a System Restore.

Video showing how to remove ransomware virus using "Safe Mode with Command Prompt" and "System Restore":

1. During your computer start process, press the F8 key on your keyboard multiple times until the Windows Advanced Options menu appears, and then select Safe Mode with Command Prompt from the list and press ENTER.

Boot your computer in Safe Mode with Command Prompt

2. When Command Prompt mode loads, enter the following line: cd restore and press ENTER.

system restore using command prompt type cd restore

3. Next, type this line: rstrui.exe and press ENTER.

system restore using command prompt rstrui.exe

4. In the opened window, click "Next".

restore system files and settings

5. Select one of the available Restore Points and click "Next" (this will restore your computer system to an earlier time and date, prior to the Guvara ransomware virus infiltrating your PC).

select a restore point

6. In the opened window, click "Yes".

run system restore

7. After restoring your computer to a previous date, download and scan your PC with recommended malware removal software to eliminate any remaining Guvara ransomware files.

To restore individual files encrypted by this ransomware, try using Windows Previous Versions feature. This method is only effective if the System Restore function was enabled on an infected operating system. Note that some variants of Guvara are known to remove Shadow Volume Copies of the files, so this method may not work on all computers.

To restore a file, right-click over it, go into Properties, and select the Previous Versions tab. If the relevant file has a Restore Point, select it and click the "Restore" button.

Restoring files encrypted by CryptoDefense

If you cannot start your computer in Safe Mode with Networking (or with Command Prompt), boot your computer using a rescue disk. Some variants of ransomware disable Safe Mode making its removal complicated. For this step, you require access to another computer.

To regain control of the files encrypted by Guvara, you can also try using a program called Shadow Explorer. More information on how to use this program is available here.

shadow explorer screenshot

To protect your computer from file encryption ransomware such as this, use reputable antivirus and anti-spyware programs. As an extra protection method, you can use programs called HitmanPro.Alert and EasySync CryptoMonitor, which artificially implant group policy objects into the registry to block rogue programs such as Guvara ransomware.

Note that Windows 10 Fall Creators Update includes "Controlled Folder Access" feature that blocks ransomware attempts to encrypt your files. By default this feature automatically protects files stored in Documents, Pictures, Videos, Music, Favorites as well as Desktop folders.

Controll Folder Access

Windows 10 users should install this update to protect their data from ransomware attacks. Here's more information on how to get this update and add additional protection layer from ransomware infections.

HitmanPro.Alert CryptoGuard - detects encryption of files and neutralises any attempts without need for user-intervention:

hitmanproalert ransomware prevention application

Malwarebytes Anti-Ransomware Beta uses advanced proactive technology that monitors ransomware activity and terminates it immediately - before reaching users' files:

malwarebytes anti-ransomware

  • The best way to avoid damage from ransomware infections is to maintain regular up-to-date backups. More information on online backup solutions and data recovery software Here.

Other tools known to remove Guvara ransomware: