So, lets explain what’s going on here. Imagine you have a Mac. Imagine you have been really diligent about keeping your copy of Adobe Flash up-to-date (Adobe is commonly targeted by the bad guys, and so Adobe has been releasing regular security updates for Flash and PDF Reader)
Now, imagine (like me) you got your copy of Snow Leopard on Friday, and have now updated your computers.
Unfortunately during the course of that update (and unknown to you) Apple downgraded your installation of Flash to an earlier version (version 10.0.23.1), which is known not to be secure and is not patched against various security vulnerabilities.
The version you should be running is the latest version of Flash Player for Mac - 10.0.32.18.
Mac users are not informed that Snow Leopard has downgraded their version of Flash without permission, and that they are now exposed to a raft of potential attacks and exploits which have been targeted on Adobe’s software in recent months.
You can update your Flash plugin here.