Private computer. Running Win8.1 & latest McAfee.
Based on the time-frame that it occurs (maybe 2-3X/mo), i'm thinking it's the Adobe Acrobat Update Service, but that's just a guess.
I've disabled this and will see if this problem recurs.
Also, next time it occurs, i'll try to figure out when the install program was laid down on the hard drive. Might give me a clue as to where it came from.