I have just downloaded the installer file from the link you posted; I have analyzed it, and it is free of malware.
If your Flash Player installation is working now (check it at http://helpx.adobe.com/flash-player/kb/find-version-flash-player.html) then you don't need to do anything.
If Flash Player is not working properly, follow these instructions:
- download the Flash Player uninstaller from http://helpx.adobe.com/flash-player/kb/uninstall-flash-player-windows.html and save it to disk;
- download the offline installer(s) from http://helpx.adobe.com/content/help/en/flash-player/kb/installation-problems-flash-player- windows.html#main-pars_header and save it/them to disk;
- close all browser and other applications, then run the downloaded uninstaller, followed by the installer(s).
That's only one scan (TrendMicro) out of 42 scanners. Not to worry - that might've been a 'false positive' from TrendMicro. What's your own 'real time protection' AV?
Do as suggested by Pat as you're surely ok.
If you still concerned try to submit the sample file to MS here >
And run MS Safety Scanner from here >