99 percent of malicious risk comes to users through their Internet browser. Malware scans the visiting user’s system for unpatched application software, so it can initiate a “silent install” The question is whether the additional protection value is worth the additional cost and effort. In most environments, it is very difficult to educate everyone in most environments. Adobe’s Flash and Acrobat Reader, Apple’s Quicktime, and Sun’s Java were among the most common unpatches programs. The trick is how to identify who in your environment really needs the training?”]
Source: https://www.csoonline.com/article/2633213/new-security-defeated-by-old-attacks.html