KillSwitch ransomware - How to remove

KillSwitch is a new ransomware virus, presumed to be based on the open source Hidden Tear project due to the way security tools recognize it (Gen:Heur.Ransom.HiddenTears.1). CryptoKill.exe is the source of malicious activity which is limited to the following location: UserProfile/Documents/test. Security researchers do not regard this variant as sophisticated, but it still poses as a threat to the Internet community.

The process of file-encryption is initiated with the help from AES-256 cipher, which creates a public key for encryption and a private one for decryption, stored in secretive hackers’ servers. In the new window that the ransomware generates as the ransom note, there are no hints about demands that hackers are making. Surprisingly, no bitcoins are required in exchange for the decryption code. Possibly, crooks might not be after money, but pure disruption.

An original extension is incorporated into digital data that becomes influenced by cryptography: .switch. Files that are marked with this label will no longer be useable as they will no longer properly launch. In total, the infection targets 17 different file-types. Before the encoding can be complemented, the payload will presumably run a scan to find compatible data. Files that end with .ott, .pdf, .PPT, .txt, .xml or .csr are only a couple of cases in point.

A malicious process will presumably run in the Windows Task Manager, but it can take a shape of a seemingly harmless procedure which will not draw any suspicion to itself. Also, additional entries in Windows Registry will also be included, allowing the payload to run automatically after every system reboot. Presumably, we expect that Windows operating systems are the main targets.

Since there are no demands for a ransom mentioned, this detected sample is rather confusing. Why bother with a virus that won’t be capable of bringing profit? Nevertheless, files can indeed become ruined and users will be interested in finding out alternative methods for file-recovery. There are a couple of things to learn about these options.

Options of file-recovery

First of all, we should state that security researchers have not produced a free decrypter. However, we do believe that this infection could be not that difficult to beat. In the meantime, you could attempt to find other solutions. The essential thing to know is that storing files in backup storages is regarded as a brilliant decision to make. Keeping digital information in multiple locations will help you recover files if one of the sources becomes corrupted. In this case, the copies that you have stored in a hard drive will be damaged.

However, if you have inserted copies of your files into an online storage or keep them safe in an USB flash drive, you should recall that you must remove the ransomware virus before those files are retrieved. KillSwitch infection might contain an element which will re-encrypt files if necessary. Therefore, we insist you either abolish the infection manually, or you use an anti-malware tool for the same purpose. Spyhunter or Hitman are one of the professional programs that could help you remove malware successfully.

Sources of ransomware explained

Different crypto-viruses can follow specific means of infiltration. In some cases malicious spam campaigns can be initiated for sake of distributing executables which will later be discovered as ransomware payloads. One specific strategy should not be emphasized more than other, as this malware can arrive from random downloads from file-sharing domains or via peer-to-peer network. Always try to avoid installing material that is not essential or is originating from unknown third-party developers.

On the last note, we should refresh your memory that paying a ransom when it comes to these crypto-viruses is a misguided step. Hackers are unreliable and might not provide victims with functional keys.

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

 

Step 2. Complete removal of KillSwitch 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 KillSwitch ransomware. You can check other tools here.  

Step 3. Restore KillSwitch 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 KillSwitch 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 KillSwitch 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.