This indicates an attack attempt to exploit a Cross-Site Scripting vulnerability in Adobe Flash Player.
The vulnerability is due to an error when the vulnerable software handles a maliciously crafted web page embedded with swf file. A remote attacker may be able to exploit this to inject arbitrary web script or HTML via a crafted web page.
Adobe Flash Player 22.214.171.124 and earlier versions for Windows and Macintosh
Adobe Flash Player 126.96.36.1999 and earlier versions for Linux
Adobe AIR 188.8.131.52 SDK and earlier versions
Adobe AIR 184.108.40.206 SDK & Compiler and earlier versions
Adobe AIR 220.127.116.11 and earlier versions for Android
Adobe AIR 18.104.22.168 and earlier versions for Windows and Macintosh
System Compromise: Remote attackers can execute arbitrary script code within the context of the target user's browser.
Apply the most recent upgrade or patch from the vendor.