How to spoof your MAC address on macOS

I don't check Dev.to that often anymore. Find me over on dancrtis.com instead.

I upgraded to Monterey recently. For some reason spoofing my MAC address to extend the time on the free WiFi priced into my $5 coffee has become a lot harder.

Before I had one magic ifconfig command to do it, now I have to run four different commands:

Disconnect from the wifi

sudo /System/Library/PrivateFrameworks/Apple80211.framework/Versions/Current/Resources/airport -z

Change my lladdr

My interface is always en0, and I just change the last digit of my MAC address. Holding option while clicking on the wifi menubar tray shows both my interface and MAC address.

sudo ifconfig <interface> lladdr <new MAC address> 

Change my ether

sudo ifconfig <interface> ether <new MAC address> 

Run ifconfig to see if the ether value for my interface changed

ifconfig

Now I can reconnect to my favorite insecure wifi. The wifi menubar tray still shows my old MAC address, but the public network sees the spoofed value from ifconfig.

Comments

[Mike Sirs]

#!/bin/zsh
if [[ $EUID -ne 0 ]]; then
echo "This script must be run with sudo." >&2
exit 1
fi

if [[ "$1" == "-h" || "$1" == "--help" ]]; then
echo "Usage: sudo ./script.sh <interface> <MAC_addr>"
echo "Sets the MAC address for the specified network interface."
echo "Arguments:"
echo " <interface> Network interface to set MAC address for."
echo " <MAC_addr> New MAC address to set."
exit 0
fi

if [[ -z "$1" || -z "$2" ]]; then
echo 'Missing <interface> and/or <MAC_addr>'
echo "Use -h or --help option for usage information."
exit 1
fi

/System/Library/PrivateFrameworks/Apple80211.framework/Versions/Current/Resources/airport -z
ifconfig "$1" lladdr "$2"
ifconfig "$1" ether "$2"