October 2010′s Patch Tuesday released a huge set of patches that addressed critical Internet Explorer issues. If you havent applied updates in awhile consider doing so ASAP.
The ten vulnerabilities differ technically, but four of the most serious ones share the same general scope and impact. These four issues involve various memory corruption flaws having to do with how IE handles certain HTML elements and objects. If an attacker can lure one of your users to a web page containing malicious web code, he could exploit any one of these four vulnerabilities to execute code on that user’s computer, inheriting that user’s privileges. Typically, Windows users have local administrative privileges. In that case, the attacker could exploit these flaws to gain complete control of the victim’s computer( Watchguard.com)
What this means:Without applying these critical updates, your system is vulnerable to attacks from computer hackers that could possibly give them complete control over your PC.