Those files would be included in either an extra.dat sent out by McAfee Labs to cover an erroneous detection or by an IT department in order to update VirusScan in some way, I would imagine, although I know nothing about Enterprise product inner workings.
You are posting in Home Products and I think you are talking about Enterprise/Business.
Can you name the McAfee product please? You may need to contact whomever does your IT,
sorry for posting here if it's incorrect. I'm not sure the product but he sent me an email with a screen shot of his mcafee and it says "About McAfee Interenet Security" and the version is 15.0 build 15.0.300 does that help at all?
I needed to ascertain whether or not it was a home or business product...it's home so I moved this to SecurityCenter. I think in this case that the person(s) whose machine(s) is/are exhibiting the behaviour should contact Technical Support directly. It is free of charge and a simple phone call away. See the link under Useful Links at the top of this page.
It's rather a coincidence that these pdf's should be converted to an actual McAfee update file as that could indicate that the wrong file is being sent in the first place, assuming updates are not what this is all about.
It's certainly a rather bizarre thing to happen.
Or they may simply need to re-associate .pdf with the right application and that varies with the operating system, and is outlined here: https://community.mcafee.com/docs/DOC-1264
Or it could be the result of an infection of some sort but that is only a wild guess. There are some tools for that here: https://community.mcafee.com/docs/DOC-2168