Comment 1 for bug 265179

The Mailman password is in no way a secure password. Mailman is intended
for a wide variety of users, most of which are unable to remember even the
simplest password ;)

The Mailman password is not used as an authentication method, but more as
a *confirmation* method. You'll get a password reminder every month or so
(if the list admin and site admin enabled that) and the only thing you use
the password for are for unsubscribing, changing your options and viewing
the private archive (if any.)

In future versions of Mailman it might be possible to use external
passwords for mailinglist subscribers, but currently the infrastructure for
that is missing. It's on the TODO list, in any case :)