Spoof Mac address with Network Manager

Spoofing MAC address is possible with Network Manager since 1.4.0. The device is sending probe requests while searching for known Wi-Fi. This broadcast contains the SSID, the devices MAC address and the signal strength, thus the device can be tracked.

Network Manager has setting for this, this setting is enabled by default:

wifi.scan-rand-mac-address=yes

When the device is connected to a network, the MAC address is restored to its original.

This configuration is responsible to change MAC at connection.

ethernet.cloned-mac-address=
wifi.cloned-mac-address=

The possible options:

  • permanent: use the devices MAC
  • preserver: dont change the devices MAC at activation
  • random: random MAC at each connection
  • stable: associate a MAC to a network, the MAC will be randomized for each network, means if you reconnect to those network, the MAC address will the same as before

To use these settings, create a new config file in /etc/NetworkManager/conf.d

nano /etc/NetworkManager/conf.d/10-mac.conf

Copy to the file:

[device-mac-randomization]
wifi.scan-rand-mac-address=yes

[connection-mac-randomization]
ethernet.cloned-mac-address=random
wifi.cloned-mac-address=random

Change random to another if you want.

Restart Network Manager:

systemctl restart NetworkManager

The fullpost can be found on Thomas Haller’s Blog