Besub ransomware removal instructions
What is Besub?
Discovered by Michael Gillespie, Besub is a ransomware-type infection that belongs to the Djvu ransomware family. After successful infiltration, Besub locks (encrypts) most stored files and appends filenames with the ".besub" extension (e.g., "sample.jpg" is renamed to "sample.jpg.besub"). Encrypted data immediately becomes unusable - this is to blackmail victims. After successfully compromising data, Besub generates a text file ("_readme.txt") and stores a copy in every existing folder.
The new text file contains a ransom-demand message, which is identical to those delivered by other ransomware infections from the Djvu family. It states that files are encrypted and that a unique decryption key is necessary to decrypt them. Unfortunately, this information is accurate. Besub employs a cryptography algorithm that generates a unique decryption key for each victim. Restoring data without these keys is impossible, and thus ransomware developers store them on a remote server to blackmail victims, demanding ransom payments for their release. To receive their keys, each victim must pay a ransom of $980. To receive payment/decryption instructions, they are encouraged to contact Besub's developers via an email address provided or telegram. It is also stated that victims who make contact within 72 hours after encryption will receive a 50% discount and the cost will drop to $490. Additionally, victims are able to send one encrypted file, which is restored and returned. Criminals do this to gain victims' trust and prove that they are capable of file decryption. In fact, these people should never be trusted, since ransomware developers often ignore victims once payments are submitted. Therefore, we strongly advise you to ignore all requests to submit payments or even contact these people. Criminals save all decryption keys on a remote server, however, there are cases whereby the server is not responding or the victim's computer has no Internet connection during encryption. In such cases, Besub encrypts data using a so-called "offline key", which is hard-coded. Therefore, attempt to restore data with the decryption tool developed by Michael Gillespie. The only other solution is to restore everything from a backup.
Screenshot of a message encouraging users to pay a ransom to decrypt their compromised data:
Besub is virtually identical to CAGO, Dcom, Coinmoney, and dozens of other ransomware-type infections. Most compromise data (typically by encryption) so that developers can blackmail victims by offering paid recovery of their files. Unfortunately, encryptions are usually performed using RSA, AES or other similar cryptographies that generate unique decryption keys. Therefore, manual decryption without involvement of the developers (not recommended) is impossible, unless the malware has bugs or flaws. Ransomware infections are one of the main reasons why you should maintain regular backups, however, store them on an unplugged storage device or a remote server, since locally stored backups are compromised together with regular data. Additionally, have multiple backup copies stored in different locations, since there is always a chance that servers and storage devices can be damaged.
How did ransomware infect my computer?
Ransomware infections are typically proliferated using trojans, fake software updaters/cracks, third party software download sources, and spam email campaigns. Trojans are essentially malicious applications that stealthily infiltrate computers and download/install additional malware. Fake updaters infect systems by exploiting outdated software bugs/flaws or simply downloading and installing malware rather than updates. The same applies to software 'cracks', which infect computers rather than providing access to paid software features. One of Besub's victims reported that this ransomware infiltrated via KMSPico, a Windows Operating System activator. Note that Peer-to-Peer (P2P) networks (e.g., torrents, eMule, etc.), freeware download/free file hosting websites, and other similar sources are used to proliferate malware by presenting it as legitimate software. In this way, users are tricked into manually downloading and installing malware. Finally, spam email campaigns are used to send hundreds of thousands of deceptive emails containing infectious attachments (various links and/or files), and deceptive messages encouraging recipients to open them. These attachments might be presented as important documents - in this way, criminals attempt to give the impression of legitimacy and increase the chance of tricking recipients into opening the files. In summary, the main reasons for computer infections are poor knowledge of these threats and careless behavior.
|Threat Type||Ransomware, Crypto Virus, Files locker|
|Detection Names (9e57.tmp.exe)||Avast (Win32:CoinminerX-gen [Trj]), BitDefender (Trojan.GenericKD.32108586), ESET-NOD32 (A Variant Of Win32/Kryptik.GUIP), Kaspersky (Trojan-Ransom.Win32.ipdel.d), Full List (VirusTotal)|
|Encrypted Files Extension||.besub|
|Ransom Demanding Message||_readme.txt|
|Cyber Criminal Contactfirstname.lastname@example.org, email@example.com, @datarestore (Telegram)|
|Symptoms||Cannot open files stored on your computer, previously functional files now have a different extension (for example, my.docx.locked). A ransom demand message is displayed on your desktop. Cyber criminals demand payment of a ransom (usually in bitcoins) to unlock your files.|
|Additional Information||This malware is designed to show fake Windows Update window, modify the Windows "hosts" file (to prevent users from accessing cyber security websites) and inject 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.|
|Malware Removal (Windows)||
To eliminate possible malware infections, scan your computer with legitimate antivirus software. Our security researchers recommend using Malwarebytes.
How to protect yourself from ransomware infections?
The key to computer safety is caution. Therefore, pay close attention when browsing the web and downloading, installing, and updating software. We strongly recommend that you think twice before opening email attachments. If the file/link is irrelevant or the sender seems suspicious, do not open anything. Furthermore, download programs from official sources only, preferably using direct download links. Third party downloaders/installers often include rogue apps, and thus such tools should not be used. Keep installed applications/operating systems up-to-date, however, use implemented functions or tools provided by the official developers only. Bear in mind that software piracy is a cyber crime and the risk of infections is extremely high, since most 'cracking tools' are fake. Therefore, never attempt to activate installed software using illegal/third party tools. Finally, have a reputable anti-virus/anti-spyware suite installed and running at all times, since this will detect and remove infections before they harm the system. If your computer is already infected with Besub, we recommend running a scan with Malwarebytes for Windows to automatically eliminate this ransomware.
Text presented in Besub ransomware text file ("_readme.txt"):
Don't worry, 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:
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" or "Junk" folder if you don't get answer more than 6 hours.
To get this software you need write on our e-mail:
Reserve e-mail address to contact us:
Our Telegram account:
Your personal ID:
Screenshot of files encrypted by Besub (".besub" extension):
Malware researcher Michael Gillespie has developed a decryption tool that might restore your data if it was encrypted using an "offline key". As mentioned, each victim gets a unique decryption key, all of which are stored on remote servers controlled by cyber criminals. These are categorized as "online keys", however, there are cases whereby the infected machine has no Internet connection or the server is timing out/not responding. If this is the case, Besub will use an "offline encryption key", which is hard-coded. Cyber criminals change offline keys periodically to prevent multiple encryptions with the same key. Michael Gillespie continually gathers offline keys and updates the decrypter, however, the chances of successful decryption are still very low, since only a very small proportion of "offline keys" have so far been gathered. You can download the decrypter by clicking this link (note that the download link remains identical, even though the decrypter is being continually updated). Your files will be restored only if the list of gathered keys includes the one that was used to encrypt your data.
Screenshot of STOP/Djvu decrypter by Michael Gillespie:
As with most ransomware from the Djvu family, Besub also displays a fake Windows update pop-up during the encryption:
IMPORTANT NOTE! - As well as encrypting data, ransomware-type infections from the Djvu malware family also install 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 done to prevent users from accessing malware security websites and seeking 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:
Besub ransomware removal:
Instant automatic malware removal:
Manual threat removal might be a lengthy and complicated process that requires advanced computer skills. Malwarebytes is a professional automatic malware removal tool that is recommended to get rid of malware. Download it by clicking the button below:
- What is Besub?
- STEP 1. Besub virus removal using safe mode with networking.
- STEP 2. Besub ransomware removal using System Restore.
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.
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.
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.
Video showing how to start Windows 10 in "Safe Mode with Networking":
Log in to the account infected with the Besub 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.
2. When Command Prompt mode loads, enter the following line: cd restore and press ENTER.
3. Next, type this line: rstrui.exe and press ENTER.
4. In the opened window, click "Next".
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 Besub ransomware virus infiltrating your PC).
6. In the opened window, click "Yes".
7. After restoring your computer to a previous date, download and scan your PC with recommended malware removal software to eliminate any remaining Besub 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 Besub 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.
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 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 Besub ransomware.
Note that Windows 10 Fall Creators Update includes a "Controlled Folder Access" feature that blocks ransomware attempts to encrypt your files. By default, this feature automatically protects files stored in the Documents, Pictures, Videos, Music, Favorites as well as Desktop folders.
Windows 10 users should install this update to protect their data from ransomware attacks. Here is more information on how to get this update and add an additional protection layer from ransomware infections.
HitmanPro.Alert CryptoGuard - detects encryption of files and neutralises any attempts without need for user-intervention:
Malwarebytes Anti-Ransomware Beta uses advanced proactive technology that monitors ransomware activity and terminates it immediately - before reaching users' files:
- 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 Besub ransomware: