Adobe Reader hasn’t fared well lately when it comes to security. But there are alternatives.
I had switched to Evince for Linux (it ships as the default with Red Hat Enterprise Linux) some time ago, and just recently followed suit on Windows. But evince has always been far from perfect on Linux, and turned out to be problematic on Windows (particularly in printing some documents). As a result I have xpdf installed as a backup on Linux, which although it uses some of the same code as evince does not rely on the gtk libraries that I think are part of the problem.
For Windows I recently started using the free Nitro Reader, which does a terrific job of both rendering and printing pdf documents. Note that the full product for business costs significantly less than the comparable Adobe suite and has a lot of features that would commend it to businesses who might otherwise choose the latter.
On both platforms I have also replaced Adobe with the free Firefox pdf.js viewer plugin for reading documents in my browser. While Firefox for Linux already offers the ability to print pages to pdf or postscript, the PrintPDF add-on gives Windows users that same functionality. From my use of these browser-based solutions you’ll probably guess that I’ve never been a big fan of plugins by desktop software vendors such as Adobe (I haven’t tried Nitro’s, and probably won’t).