A new type of Trojan has been reported to utilize an old devastating method that corrupts Windows and restarts the computer. The Trojan is known as Disakil (Symantec), and it is not very widespread. However, this particular Trojan horse may be devastating to your hard drive. In case, you try to boot your system, and you see the “BOOTMGR is Missing” message, chances are you have been hit by the variants of this malware. In case this is true, you should not format your drive and look for alternatives to salvage your data.
Name | KillDisk Disakil |
Type | KillDisk Trojan |
Short Description | The cyber-threat directly compromises the operating system and files below 1.1 MB of the infected PC. |
Symptoms | The user may witness sudden restart after which his OS may fail to start and display a DOS error message instead. (ex. “BOOTMGR is missing”) |
Distribution Method | Via other malware on the computer or the below mentioned methods in the “Distribution” paragraph. |
Detection Tool | Download Malware Removal Tool, to See If Your System Has Been Affected by malware |
User Experience | Join our forum to discuss KillDisk Disakil. |
KillDisk Disakil Trojan – Spread
Similar to every other Trojan Horse out there, this one may be distributed via four different ways:
- Via other malware or unwanted software installed on your computer.
- Via malicious URLs.
- Through malicious email or other messages’ attachments.
- If someone deliberately installed in on the computer.
KillDisk Disakil Trojan In Detail
Symantec Security Response researchers have established that its malicious executable that carries the payload has been downloaded and ran on the victim’s computer, the Trojan begins by making a .tmp file with random numbers or letters or both. The file is located in the %Temp% folder. KillDisk Disakil then deletes this subkey from the Windows Registry:
→“HKEY_LOCAL_MACHINE\Software\MicrosoftApplicationMgr”
After doing so, the malware begins to overwrite files. First, it overwrites a chunk of the data at the start of a file, called sec_service.exe.
After doing so, it begins to target smaller than 1.1 MB in case they are located in removable as well as fixed drives. The files it may target and overwrite may be of the following extensions:
→.accdb .bin .bmp .boot .cfg .crt .db .dbf .djvu .doc .docx .exe .ini .iso .jar .jpeg .jpg .lib .mdb .mdf .msi .pdf .ppt .pptx .rar .rtf .sql .tib .tiff .txt .vhd .xls .xlsx .xml .zip
The cyber-threat will also begin to overwrite bytes of the data in vital files that are located in the %Windows%. It targets these extensions:
→.dll .exe .xml .ttf .nfo .fon .ini .cfg .boot .jar
Meanwhile, this nasty malware may begin to end important processes. It leaves only some of them intact so that it can operate:
→ 73.exe audiodg.exe conhost.exe csrss.exe dwm.exe explorer.exe komut.exe lsass.exe lsm.exe services.exe shutdown.exe smss.exe spoolss.exe spoolsv.exe svchost.exe taskhost.exe wininit.exe winlogon.exe wuauclt.exe
Finally, this malware is capable of performing malicious activities on the computer. They may vary:
- Delete or modify the data in a service, called sec_service.
- Terminate sec_service and make it inactive.
- Delete the MBR(Master Boot Record) of the drives on the compromised PC, hence render them unusable.
- Erase the logs of the apps, security settings, setups, system events.
- Reset your computer.
These modifications may result in the destruction of the affected operating system by simply rendering system files unusable.
Remove KillDisk Trojan and Protect Your Files
Since this Trojan corrupts Windows, you have two primary options. Before seeing them, you must backup all of your data. To do this, you should seek to boot a live operating system that can unlock files on your drives without having access to them. One example of such Windows OS is originating from Russia and is called Windows 7 LiveCD by Xemom1. In it, the OS has an embedded AntiWinlocker, which will allow you to access your files. Bear in mind that this is just an example and it may not be safe for work. There are many other live OS’s out there that also have AntiWinlocker. Google is your friend.
Option 1: To try and repair your Windows OS.
To do that, you need to boot into the Advanced options menu and select the Repair your PC option. Here are instructions on how to work with the Advanced Startup Menu. From there, in the advanced menu, you should see several restoration options. From them, choose Advanced Options>Startup Repair. But to restore from an image or any other way you must have the original Windows CD with you.
Option 2: To extract your files and completely reinstall Windows OS.
This option is the easier one. Simply copy your files using a live OS (as the example above) and reinstall Windows by again booting in the advanced startup menu, but, this time, choosing the Reset Your PC preference.
Ofcourse you may try to boot in Safe Mode and scan your computer using an anti-malware tool which will remove the Trojan before attempting the methods above. This can happen if you go to Advanced Options>Startup Settings and select Safe Mode. You may still try doing this it is highly unlikely that you will succeed, so we recommend just to copy your data and reinstall Windows just to be safe. And then download a reliable anti-malware tool which will protect your computer from attacks by a KillDisk Trojan in the future.
N.B. In case you manage to find your files, and they are damaged, try repairing your Windows without formatting your hard drive and then try to restore earlier versions. Here are several file recovery options:
Also, to protect your files in the future, we have prepared instructions on how to back them up the proper way:
- Guide 1: How to Remove KillDisk Disakil from Windows.
- Guide 2: Get rid of KillDisk Disakil from Mac OS X.
- Guide 3: Remove KillDisk Disakil from Google Chrome.
- Guide 4: Erase KillDisk Disakil from Mozilla Firefox.
- Guide 5: Uninstall KillDisk Disakil from Microsoft Edge.
- Guide 6: Remove KillDisk Disakil from Safari.
- Guide 7: Eliminate KillDisk Disakil from Internet Explorer.
Windows Mac OS X Google Chrome Mozilla Firefox Microsoft Edge Safari Internet Explorer
How to Remove KillDisk Disakil from Windows.
Step 1: Boot Your PC In Safe Mode to isolate and remove KillDisk Disakil





Step 2: Uninstall KillDisk Disakil and related software from Windows
Here is a method in few easy steps that should be able to uninstall most programs. No matter if you are using Windows 10, 8, 7, Vista or XP, those steps will get the job done. Dragging the program or its folder to the recycle bin can be a very bad decision. If you do that, bits and pieces of the program are left behind, and that can lead to unstable work of your PC, errors with the file type associations and other unpleasant activities. The proper way to get a program off your computer is to Uninstall it. To do that:



Step 3: Clean any registries, created by KillDisk Disakil on your computer.
The usually targeted registries of Windows machines are the following:
- HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\Run
- HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run
- HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\RunOnce
- HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\RunOnce
You can access them by opening the Windows registry editor and deleting any values, created by KillDisk Disakil there. This can happen by following the steps underneath:



Before starting "Step 4", please boot back into Normal mode, in case you are currently in Safe Mode.
This will enable you to install and use SpyHunter 5 successfully.
Windows Mac OS X Google Chrome Mozilla Firefox Microsoft Edge Safari Internet Explorer
Get rid of KillDisk Disakil from Mac OS X.
Step 1: Uninstall KillDisk Disakil and remove related files and objects
1. Hit the ⇧+⌘+U keys to open Utilities. Another way is to click on “Go” and then click “Utilities”, like the image below shows:
- Go to Finder.
- In the search bar type the name of the app that you want to remove.
- Above the search bar change the two drop down menus to “System Files” and “Are Included” so that you can see all of the files associated with the application you want to remove. Bear in mind that some of the files may not be related to the app so be very careful which files you delete.
- If all of the files are related, hold the ⌘+A buttons to select them and then drive them to “Trash”.
In case you cannot remove KillDisk Disakil via Step 1 above:
In case you cannot find the virus files and objects in your Applications or other places we have shown above, you can manually look for them in the Libraries of your Mac. But before doing this, please read the disclaimer below:
You can repeat the same procedure with the following other Library directories:
→ ~/Library/LaunchAgents
/Library/LaunchDaemons
Tip: ~ is there on purpose, because it leads to more LaunchAgents.
Step 2: Scan for and remove KillDisk Disakil files from your Mac
When you are facing problems on your Mac as a result of unwanted scripts and programs such as KillDisk Disakil, the recommended way of eliminating the threat is by using an anti-malware program. SpyHunter for Mac offers advanced security features along with other modules that will improve your Mac’s security and protect it in the future.
Windows Mac OS X Google Chrome Mozilla Firefox Microsoft Edge Safari Internet Explorer
Remove KillDisk Disakil from Google Chrome.
Step 1: Start Google Chrome and open the drop menu
Step 2: Move the cursor over "Tools" and then from the extended menu choose "Extensions"
Step 3: From the opened "Extensions" menu locate the unwanted extension and click on its "Remove" button.
Step 4: After the extension is removed, restart Google Chrome by closing it from the red "X" button at the top right corner and start it again.
Windows Mac OS X Google Chrome Mozilla Firefox Microsoft Edge Safari Internet Explorer
Erase KillDisk Disakil from Mozilla Firefox.
Step 1: Start Mozilla Firefox. Open the menu window
Step 2: Select the "Add-ons" icon from the menu.
Step 3: Select the unwanted extension and click "Remove"
Step 4: After the extension is removed, restart Mozilla Firefox by closing it from the red "X" button at the top right corner and start it again.
Windows Mac OS X Google Chrome Mozilla Firefox Microsoft Edge Safari Internet Explorer
Uninstall KillDisk Disakil from Microsoft Edge.
Step 1: Start Edge browser.
Step 2: Open the drop menu by clicking on the icon at the top right corner.
Step 3: From the drop menu select "Extensions".
Step 4: Choose the suspected malicious extension you want to remove and then click on the gear icon.
Step 5: Remove the malicious extension by scrolling down and then clicking on Uninstall.
Windows Mac OS X Google Chrome Mozilla Firefox Microsoft Edge Safari Internet Explorer
Remove KillDisk Disakil from Safari.
Step 1: Start the Safari app.
Step 2: After hovering your mouse cursor to the top of the screen, click on the Safari text to open its drop down menu.
Step 3: From the menu, click on "Preferences".
Step 4: After that, select the 'Extensions' Tab.
Step 5: Click once on the extension you want to remove.
Step 6: Click 'Uninstall'.
A pop-up window will appear asking for confirmation to uninstall the extension. Select 'Uninstall' again, and the KillDisk Disakil will be removed.
Windows Mac OS X Google Chrome Mozilla Firefox Microsoft Edge Safari Internet Explorer
Eliminate KillDisk Disakil from Internet Explorer.
Step 1: Start Internet Explorer.
Step 2: Click on the gear icon labeled 'Tools' to open the drop menu and select 'Manage Add-ons'
Step 3: In the 'Manage Add-ons' window.
Step 4: Select the extension you want to remove and then click 'Disable'. A pop-up window will appear to inform you that you are about to disable the selected extension, and some more add-ons might be disabled as well. Leave all the boxes checked, and click 'Disable'.
Step 5: After the unwanted extension has been removed, restart Internet Explorer by closing it from the red 'X' button located at the top right corner and start it again.