I've just gone through the cycle of updating Flash:-
a) I got the usual message about there being an update available
b) having accepted that I was re-directed to a Web-Page to initiate a download.
c) within that Web-Page (although not particularly noticeable) was a tick-box confirming McAfee.
d) un-ticking & accepting downloaded the file
e) Once downloaded, I then had to run it.
f) During the install process I, yet again, had to prevent it setting up auto-update!