I know that flashplayer-plugin is not packaged or distributed by CentOS but there's a RedHat "Critical" advisory at https://rhn.redhat.com/errata/RHSA-2005-835.html that I don't believe has been mentioned here. There is no CentOS rpm that I can find but the binary of version 7.0.61 is available from http://www.macromedia.com/shockwave/download/download.cgi?P1_Prod_Version=ShockwaveFlash and is pretty much a no-talent install. (Sure would be nice if rpm knew about it, though...)