Lisp Ransomware - How to remove

Lisp is file-locking ransomware that renames those files by adding a second extension, “lisp”. In addition, it brings spyware and adware to the infected computer.

Lisp is part of the Djvu ransomware family, together with Sglh, Vvoa, and other infections.

Lisp in short:

Classification	Ransomware.
How Lisp affects the computer	It breaks files, it installs other malware, it deletes backup data.
How to restore the files	Restore them from your backup, recover deleted data, repair the files, use the decryptor.
Removing Lisp	Remove Lisp and other malware with antivirus tools (Spyhunter, others) after unblocking security sites and installing required updates.

How Lisp ransomware works

Additional malware

Lisp gets detected by antivirus programs by names like Trojan, Ransom, Kryptik, Malware, and others: Virustotal.com.

Lisp spreads with pirated software. People who use unreliable websites to illegitimately download free software risk getting malware on their computers.

In addition, those infected programs also bring spyware and adware. These malicious programs steal private information (such as the passwords saved in web browsers) off of the infected computer and force browsers to display additional ads.

Besides installing all this malware, Lisp also makes some unwanted changes in the computer:

• It deletes restore points and shadow volume copies.
• It blocks various cybersecurity websites.
• It stops antivirus processes and deletes some of their required files.
• It may disable the Task Manager, Registry Editor, and other tools that can be used to stop malware.

Not to mention its main feature – breaking all the files that it can find.

Overall, Lisp can do a lot of harm to the infected computer.

File encryption

After a Lisp attack, your files may be a bit broken:

• They can’t be opened. Most of them, at least.
• Their contents are full of random symbols. You can see that if, for example, you force a text file to open in your Notepad.
• The names of these files have been changed to include a second file type extension, “lisp”. For instance, “song.mp3” becomes “song.mp3.lisp”.

Lisp uses cryptography to break user files. It secures them with a password and then encrypts the password. As a result, it’s impossible to decrypt the files without the decryption key which is only known to the criminals behind Lisp. It is also to guess that key. And it is extremely unlikely that you share this key with another victim of Lisp ransomware.

Nowadays, ransomware viruses have started to steal files before encrypting them. However, it is unlikely that Lisp does this. Data theft is used against big companies and organizations, while Lisp ransomware targets individual PC users.

Can the files be restored?

Obviously, Lisp needs to be deleted, but it won’t bring your files back. Can you get your files back without having to pay a $490/$980 ransom to the criminals behind Lisp?

If you had a backup of your data, then that’s all you need. Just remove Lisp and the other malware first. You can delete the encrypted files, as well.

If you don’t have backups, then your options are not great:

• Use a data recovery program to restore backup data and other data that Lisp deleted. These programs can detect and restore some deleted files, but it’s complicated. With continued use of the infected drive, the chances of restoring any deleted data go down.
• Repair the files yourself. Lisp encrypts some files only partially – the larger a file, the more data on it remains unencrypted and can be recovered. Although, it is complicated.
• If there’s a chance that your files can be decrypted by using someone else’s decryption key, the Emsisoft decryptor will tell you.

Don’t fall for scammers that promise to fix your files for a fee. Decryption is impossible without the correct decryption key, which is only known to the cybercriminals behind Lisp. Djvu ransomware is well known and well studied, and sadly, there is no miracle cure for it.

How to remove Lisp ransomware

To avoid any more files being encrypted, Lisp ransomware needs to be deleted. If it came with other files, those files need to be deleted. The additional malware that came with Lisp also needs to be removed. Use an antivirus program that you trust (such as Spyhunter, but make sure that it’s got the latest updates.

Only the encrypted files – those with the “.lisp” extension – don’t need to be removed, as they’re not dangerous.

Important -- edit the hosts file to unblock security websites

TL DR : The hosts file is edited to block security sites Before the virus can be removed, it's necessary to fix the hosts file (the file which controls which addresses connect to which IPs). That is the reason the majority of security websites is inaccessible when infected with this particular parasite. This infection edits this file to stop certain websites, including anti-malware download sites, from being accessed from the infected computer, making browsers return the "This site can't be reached" error. Luckily, it's trivial to fix the file and remove the edits that were made to it.

Find and edit the hosts file

The hosts file can be found on C:/Windows/System32/Drivers/etc/hosts. If you don't see it, change the settings to see hidden files.

1. In the Start Menu, search for Control Panel.
2. In the Control Panel, find Appearance and Personalization.
3. Select Folder Options.
4. Open the View tab.
5. Open Advanced settings.
6. Select "Show hidden files...".
7. Select OK.

Open this file with administrator privileges.

1. Open the Start Menu and enter "notepad".
2. When Notepad shows up in the result, right-click on it.
3. In the menu, choose "Run as administrator"
4. File->Open and browse for the hosts file.

The hosts file should look like this: Delete additional lines that they connect various domain names to the wrong IP address. Save the file.

Download and run the antivirus program

After that, download antivirus programs and use them to remove the ransomware, the trojan, and other malware. Spyhunter (https://www.2-viruses.com/reviews/spyhunter/dwnld/).

Automatic Malware removal tools

How to recover Lisp 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 Lisp Ransomware has infiltrated to your system and then click “Next”.
• To start System restore click “Yes”.

 

Step 2. Complete removal of Lisp 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 Lisp Ransomware. You can check other tools here.  

Step 3. Restore Lisp 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 Lisp 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 Lisp 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.