I read that there is a fake KM Player doing the rounds at different websites, which when installed installs some Malware

source:
You Must Be Registered and Logged On To View "URL" BBCode Contents...


A quick google search gave me a couple of links

KMPlayer forum:
You Must Be Registered and Logged On To View "URL" BBCode Contents...


Malwarebytes forum:
You Must Be Registered and Logged On To View "URL" BBCode Contents...


I would recommend KMPlayer users to upload the setup files to virustotal or virscan or jotti's malware scanner to make sure if it is safe.

If you already have KMPlayer on your PC, run a scan with your Anti-virus or Malwarebytes (though I doubt this would help, since Mbam haven't updated their forum thread)