The Papa.A variant has a serious bug in it's code and it does not work. This bug was fixed in the Papa.B variant which is able to spread via Internet.
Every time when a XLS file infected by Papa is opened, it emails a copy of itself via email, using Microsoft Outlook, to the first 60 people in the Address Book.
The email sent by the worm looks like this:
From: (name of infected user)
To: (60 names from alias list of the infected user)
Subject: Fwd: Workbook from all.net and Fred Cohen
Urgent info inside.
Disregard macro warning.
If the attached file is opened, it looks like this:
It is important to notice that Dr. Fred Cohen and the website at all.net have nothing to do with the worm. Authors of this worm simply want to harass him. In addition, the worm will try to overload the all.net web server by repeatedly pinging it.
The worm won't spread further to other XLS files, it just mails XPASS.XLS around.