[CentOS] Security patches list not showing

Thu Apr 21 13:22:47 UTC 2016
Selvin Durai Masilamani <mselvin89 at yahoo.com>

Hi team,

Security patches isn't not showing from Centos 5,6 and 7. 

Tried Steps: 

First I installed yum install yum-security package

Then I tried yum update --security

But getting these message 

No need to update for security patches , 80 available