Software Engineering Institute

Adobe Flash Player is a player for the Flash media format and enables frame-based animations with sound to be viewed within a web browser.

According to Adobe:

The AllowScriptAccess parameter of the Macromedia Flash Player controls the ability to perform outbound scripting from within a Flash SWF.
A vulnerability in Adobe Flash Player may allow an attacker to circumvent the allowScriptAccess parameter. The specific cause of the underlying defect is not known.

By convincing a victim to view a HTML document (web page, HTML email) containing specially crafted Adobe Flash SWF file, an attacker could access content in a different security domain than the one containing the attacker's document.

Upgrade Flash Player
Adobe has addressed this issue in Adobe Flash Player 9.0.16.0.

Apply updates

Users who are unable to upgrade to Adobe Flash Player 9.0.16.0 should apply the appropriate player update listed in Adobe Security Bulletin APSB06-11.

Users running operating systems that do not support Adobe Flash Player 8 should refer to the updates in Adobe's Flash Player TechNote.

Microsoft has released an update to address this issue. See Microsoft Security Bulletin MS06-069 for more details.

Disable Adobe Flash Player in your web browser

Until it is possible to upgrade to Adobe Flash Player 9.0.16.0 or apply the appropriate update, disabling Adobe Flash Player in the web browser will reduce the chances of exploitation.