This indicates an attack attempt to exploit a Heap Overflow vulnerability in Adobe Flash Player.
The vulnerability is due to an error when the vulnerable software handles a maliciously crafted SWF file. A remote attacker may be able to exploit this to execute arbitrary code within the context of the affected application, via a crafted SWF file.
Adobe Flash Player Desktop Runtime 220.127.116.11 on Windows and Macintosh
Adobe Flash Player Extended Support Release 18.104.22.1686 on Windows and Macintosh
Adobe Flash Player for Google Chrome 22.214.171.124 on Windows, Macintosh, Linux and ChromeOS
Adobe Flash Player for Microsoft Edge and Internet Explorer 11 126.96.36.199 on Windows 10 and 8.1
Adobe Flash Player for Linux 188.8.131.522 on Linux
System Compromise: Remote attackers can gain control of vulnerable systems.
Apply the most recent upgrade or patch from the vendor.