What qualifies a paper/dissertation to received the status 'published' This is for a master's level, if a department decides to publish students' dissertations, does that qualify to be named as a published paper? or does it have to be a journal with certain impact factor?

Edit: if online publications are considered ok, can they be added to a resume in 'publication' sections?
The exact meaning of the word "publication" is dependent on context.  In some contexts, it might be understood to include only articles accepted in peer-reviewed journals or conference proceedings.  (Impact factor is not usually a consideration here.)  In other contexts, it might also include books, dissertations, lecture notes, arXiv preprints, and other documents that have been made publicly available.

So whether a dissertation should be "named as a published paper" depends on your audience.

For academic CVs, people often create two sections: one that lists peer-reviewed publications, and another that lists non-peer-reviewed writings.  This removes any ambiguity.  A master's dissertation would go in the non-peer-reviewed section.

If you are writing a resume for the business world, standards might be different.  http://workplace.stackexchange.com might be a better place to ask about that situation.