It is primarily sought for "End of Life" devices that no longer receive official updates from TomTom. Official & Safe Alternatives

If you are trying to update your GPS, it is recommended to use official channels to avoid malware:

Use the official TomTom HOME or MyDrive Connect software to check for available updates.

Check the TomTom Support Page to see if your device still qualifies for "Lifetime" map updates. TomTom Forums

It often includes scripts to patch the device's firmware (Navcore) to allow it to recognize these maps.