Adobe released a security bulletin: APSB08-11.

According to Adobe summary:

Critical vulnerabilities have been identified in Adobe Flash Player that could allow an attacker who successfully exploits these potential vulnerabilities to take control of the affected system. A malicious SWF must be loaded in Flash Player by the user for an attacker to exploit these potential vulnerabilities. It is recommended users update to the most current version of Flash Player available for their operating system.

Affected software versions:Adobe Flash Player 9.0.115.0 and earlier, and 8.0.39.0 and earlier

Adobe recommends affected users upgrade to version 9.0.124.0

How to know my Adobe Flash Player version?
Visit here: http://www.adobe.com/products/flash/about/