It does not import passwords.
Here’s what it pulls from the user field. You can have a look a the code here. Even if you are not a programmer, you might be able to glean what is imported by looking at the names of the fields. For example:
"SELECT user_id id, username, email, custom_title title, register_date created_at,
last_activity last_visit_time, user_group_id, is_moderator, is_admin, is_staff
lets you see what gets pulled out of the XenForo database.
You might check out this thread, which describes a migrate-password plugin and how to write (or modify) an importer to migrate the passwords.
If you’d like someone to modify the XenFro importer, you can make an offer in the #marketplace.