These days, two vulnerabilities in Adobe Flash Payer, which is part of Internet Explorer, have come to light. One of them has been fixed and an update to Windows Update (3033408) is available, but the fix for the other one will not be ready until next week. However, a dangerous program using this publicly known vulnerability is already spreading through advertising systems. Therefore, it is quite reasonable to disable Flash in the browser. Just turn on the ActiveX Filtering feature.
A browser vulnerability manifests itself in such a way that if you visit an attacker’s website, it can take control of your computer. It can be used to read all your documents, it can record your password to internet banking, for example, or it can involve your computer in a mass attack against a company or government.
The vulnerability of image or Flash decoding is particularly dangerous in that sites load them from unknown sources through advertising systems. Thus, an attacker can attack in this way not from tens of thousands or hundreds of thousands of websites that an unsuspecting user can visit for a long time and consider trustworthy.