This indicates an attack attempt to exploit a vulnerability in Adobe Flash Player.
This signature detects malicious obfuscated SWF files. Flash exploits can be and are often highly obfuscated with software like secureSWF. An attacker can launch exploits by tricking an unsuspecting user into visiting a malicious webpage and execute arbitrary code within the context of the application, via a crafted SWF file.
Adobe Flash Player
System Compromise: Remote attackers can gain control of vulnerable system.
Update to the latest version from the vendor.