killr

What is this?

killr is a super simple remote killswitch for Windows PCs.

All code is under AGPLv3.

Installation

Download the following files and keep them all in the same directory:

 1. index1.html - primary html doc
 2. index2.html - secondary html doc
 3. killr.cmd   - main script
 4. nc.exe      - netcat executable compiled for Windows
 5. pass.txt    - text file with your passphrase
 6. res.txt     - HTML headers

killr requires netcat (nc.exe). You can compile it yourself, if you wish. Get the code here.

Next:

1. edit pass.txt to contain only your password.
2. edit the port and comfile variables at the top of killr.cmd.
3. create a scheduled task to run killr.cmd on startup.

comfile should be the path of a script or executable which gets called when the killswitch is activated.
port should be the port on which killr listens.

Invocation

killr is invoked by sending a GET request: hostname:port/?password=<password>.

If you visit https://hostname:port/ in your browser, it should show you a form which allows you to do the same thing.

When killr is invoked, it executes the script defined in comfile, stops accepting any requests, and will only display a static HTML page.

When the killswitch is activated, it deletes the password file, forcing you to set up a new one in order to reset the killswitch. This is by design. Because your connection with killr is not encrypted, a third party can get your password through a MITM attack. For this reason, please choose a new and unique password each time you reset killr.

Logs

You can access killr's logs in killr_log.txt.

Temporary Files

killr makes two temporary files: __input and __pas. These are safe to delete at any point, they'll just be recreated.