[CentOS] Apache httpd-2.2.15 updates

Hello,

I am working on a CentOS Linux 2.6.32-71.el6.x86_64 system.
I noticed that the system came with httpd-2.2.15-6 installed.
After I run 'yum update' I get httpd-2.2.15-9.

I did some research on the Internet, but can't find the following
information: are most of the security fixes that appear in httpd-2.2.21
applied to the update on httpd-2.2.15-9?

There was a security fix just last August, the CVE-2011-3192 on Range and
DoS. I don't imagine that this is in the 2.2.15-9. Do you have plans to
provide this patch in the repository so that 'yum update httpd*' would get
this patch?

Thank you in advance,

  Dirce Richards
  Systems Engineer, GlobalCerts