Invader Informant

CLI tool for Mac OS to automate network scans and notify, using ntfy.sh, of any new or dropped connections on your network.

The script will scan for your particular network IP using ipconfig and then scan the subnet for devices/hosts using nmap. Following, it will look for differences in connected hosts logs and send the information to your ntfy server.

Dependencies:

Install Nmap -> https://nmap.org/download#macosx

or using homebrew

brew install nmap 

Install Instructions

1. Install script to the default mac os PATH location /usr/local/bin

 curl -L https://raw.githubusercontent.com/patricksthannon/InvaderInformant/refs/heads/main/InvaderInformant.sh -o /usr/local/bin/InvaderInformant.sh && chmod +x /usr/local/bin/InvaderInformant.sh

2. Edit script to add your ntfy server ip and topic name

topic=your_ntfy_topic_here
notifyserver=your_ntfy_server_ip_here

Edit using Vim
vim /usr/local/bin/InvaderInformant.sh

Or Edit using VSCode
code /usr/local/bin/InvaderInformant.sh

3. Test script

InvaderInformant.sh

4. Add on a cron schedule

crontab -e 

add a cronjob (every 5 minutes as the example or use a Crontab Generator)

Press i

*/5 * * * * /usr/local/bin/InvaderInformant.sh

Save and quit your crontab script schedule

Press escape

:wq

Credits 🙌

This is an modified version of notify_me_the_intruders by nothingbutlucas

If you like this project, consider buying me a coffee to keep me motivated! I appreciate it!