Adobe has released a new version, 11·1·102·55, of its Flash Player, for Windows, Linux, Mac OS X, and Solaris. The new version contains bug fixes, and also patches 12 identified security vulnerabilities, which are detailed in the accompanying Security Bulletin [APSB11-28]. Further information is also available in the Release Notes.
I recommend updating your system to the new version as soon as you conveniently can. You can download the new version from the Flash download page.
Update Friday, 11 November, 16:14 EST
If you need to check the version of Flash Player that you are using, visit this Adobe page. It will also show you the most current versions by platform.