Adobe Reader is free. It is also one of the biggest magnets for attack on your computer. In fact, it is likely only behind Adobe Flash and Oracle Java. Yes, these are not good times for Adobe — the company is in an endless cycle of security updates in a desperate attempt to stay one step ahead of the bad guys, and frequently failing to do so.
So what do you do? Well, you may not be able to avoid Flash and Java, but you certainly have plenty of options when it comes to PDF readers.