This indicates an attack attempt against a code-execution vulnerability in Adobe Flash Player.
The vulnerability is caused by an error when the vulnerable software handles a malicious .swf file. It allows a remote attacker to execute arbitrary code via sending a crafted .swf file.
Adobe Flash Player 10.0.45.2 and prior versions
System Compromise: Remote attackers can gain control of vulnerable systems.
Refer to the vendor's advisory for updates: