YUM Update without upgrade to minor release

Hello everyone,

We recently upgraded one of our RHEL 5.8 servers using the yum update command.  There were over 200 items in the list and we went ahead with all of them. Unbeknownst to us the system was upgraded to the next minor release (5.9) and is now unsupported by some of our hardware vendors.

The question I have is:  is it possible to update packages for the most important security fixes without upgrading to the minor version of the software?  Is there a best practice approach to using yum?  As you can imagine the above scenario is not optimal to say the least.

Thanks for your help in advance!

Ilya