A kill switch is a VPN security feature that automatically cuts off your internet connection if your VPN server disconnects.
Kill switch is a security measure used by some VPNs to ensure that if the VPN server goes offline, the internet connection will automatically stop. This allows for added protection against malware and hackers who may try to steal your data while you are connected.
A kill switch is an important feature of any paid VPN service, but it's especially crucial for free VPN services because they can't protect their customers without one. If something goes wrong with a free VPN's servers or other infrastructure, the user could be left unprotected.
If you have a kill switch on your smartphone, then any time you lose control of the device or someone else gains access to it without your knowledge, they will not be able to do anything with it until you enter an unlock code.
Benefits of using a Kill Switch
If you've used mobile devices long enough, you've probably realized that they are prone to theft. Although there are many security options available today to protect your phone or tablet from theft such as pattern locks and more advanced features like facial recognition, none of those is actually foolproof. This is mainly because people can still find ways to unlock the phone regardless of the security features.
In order to protect your device from any unauthorized user, you need something that's designed to qualify as a foolproof security feature. This is where Google comes in with its “kill switch” feature.
Although it isn't exactly a kill switch per se, it does add an extra layer of protection that not only protects your device from thieves but also prevents it from getting resold which makes the kill switch an excellent anti-theft tool. The VPN kill switches check the system called network lock to ensure private internet access and internet traffic. That's how a VPN kill switch works for VPN providers.
The mechanism behind how malware developers implement kill switches inside their virus varies from one virus to another. There are many ways they can do it but the most popular methods are as follows:
This kind of detection is used by malware developers to identify security products installed on a victim machine that might have been previously detected. This method gets activated by scanning folders, running processes, and network activity for known signatures of security products. Then this information gets sent to the server and if it detects any security product, then it terminates itself.
Searching for filename:
This method is based on searching specific files or folders which often contain security products like “Kaspersky”, “Bitdefender” etc. If these files are detected in a system, then the malware executable gets terminated.
Reading registry keys:
This method is also based on searching for specific registry keys which refer to security products installed in the victim's computer such as “HKEY_CURRENT_USERSoftwareBitdefender” and so on. If these registry keys are detected malware executable gets terminated or disabled to avoid getting caught by its developer.
Command and control server:
The attacker first sets up a command and control server where the virus sends all important information about the infected system such as bot id, IP address, user name, etc. After that, the C& C server sends back a key to the killing switch which is activated if it detects any changes in this information like prefix change (ex: before it sends “a” and after sending “b” or something else) because these changes mean that the command and control server has been hacked.
The virus often saves its decryption key in a system registry which gets activated if any changes are detected in the code of the virus executable (ex: 1+1=2).
It is important to note that not only does Ransomware uses kill switches in their viruses but also many other malware like banking trojans which kill themselves if it detects security products such as sandboxes and virtual machines.
This means that if you've got a feature called “Factory Reset Protection,” it would be a better idea to use a feature that allows you to remotely wipe all the data on your device so there's no way for anyone to get access to them. This is where the kill switch comes in, allowing you to wipe out all of your personal information from your tablet or phone remotely.
An application-level kill switch protocol may not sound as safe as a system-level kill switch, but it's arguably the better option if the VPN connection fails. If the VPN connection suddenly drops it will prevent leaks.
What problem does Kill Switch solve?
The kill switch feature allows you to reset your device remotely as well as remove all of the personal data from it. In case you've forgotten about a factory reset protection (FRP) enabled phone somewhere and someone manages to find a VPN connection, without the kill switch that person will be able to use your device or resell it since they can access all of its contents.
With many VPN kill switches, however, you can remove all of your personal data from it so that person won't be able to use or resell your device since it will be completely clean after being reset without having access to any of the phone's contents. The VPN connection drops within a VPN server for an internet service provider.