When a base64 encoded username:password pair ends in = it should be transmitted to the /login endpoint as %3D. However, the Arris web interface doesn't do this and the /login endpoint does not support it. Manually appending the base64 value to the URL works.
When a base64 encoded username:password pair ends in = it should be transmitted to the /login endpoint as %3D. However, the Arris web interface doesn't do this and the /login endpoint does not support it. Manually appending the base64 value to the URL works.