The most recent Flash Player for Windows is 11.4.x, for Linux it is 11.2.x. Are there already any security issues? Are security patches still released for the Linux versions?
Adobe has changed their support for Flash on Linux.
NOTE: Adobe Flash Player 11.2 will be the last version to target Linux as a supported platform. Adobe will continue to provide security backports to Flash Player 11.2 for Linux.
Adobe is saying that they will provide security updates:
Mozilla, Firefox, SeaMonkey (Flash Player 11.2 is the last supported Flash Player version for Linux. Adobe will continue to provide security updates.)
---- content merged from Tom Brossman's answer ----
Instead of a standalone plugin, the latest version is available only in Google's Chrome browser for Linux.
Reading their press release from the marketing team, it seems that they are 'partnering' with Google.
Flash 11.2 regularly receives security updates, backported from the latest version by Adobe. These are installed through Update Manager.
Flash on Linux is not as "abandoned" as some suggest.