Privileged ports

On Unix systems (Linux and Mac OS), only programs running as root may bind to ports < 1024. Thus, netsleuth will fail to listen for HTTP(s) on ports 80/443 and you will be unable to add local mode proxy targets. (Windows has no such restriction; you can skip this section.)

While you can start the netsleuth daemon using sudo, this is not recommended due to the security problems associated with running the daemon as root. Instead, you should utilize netsleuth's builtin authbind support.

When you open the GUI on http://localhost:9000, netsleuth will notify you if it needs additional privileges to listen on privileged ports. Click the button and netsleuth will ask for root permissions to install and configure authbind.

On Linux systems, it will attempt to install the authbind package using apt-get. If your system uses a different package manager, you'll need to manually install authbind.

On Mac, netsleuth will download and install a x64 binary release. It also configures your loopback interface to allow listening on,, and so on. (This is not necessary on other platforms as they already allow listening on

On all platforms, netsleuth will configure authbind to allow your user account to listen on ports 80 and 443.

The setup script can also be run from the command line:

sudo netsleuth setup

The exact modifications that are made to your system can be found in lib/system-setup.js.