Adobe has admitted there is a critical zero day bug in its Flash Player, Acrobat and Adobe Reader applications. As well as potentially causing a crash, the bug also could allow an attacker to remotely take control of a computer. The problem exists in Windows and Macintosh computers alike. Some Android and some Linux systems are also affected, depending on the versions of the Adobe products involved.
If you use any of these products (and most of us do), you can learn more about the bug if you read any of the hundreds of articles available. Start at http://goo.gl/7ENC