Sorry, one more thing. I followed
Loaded plugins: fastestmirror, security
Loading mirror speeds from cached hostfile
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Important CentOS nss Update
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Update ID : CESA_2013__1791
Release : CentOS 5
Type : security
Status : stable
Issued : 2013-12-05 17:45:58
Description : Important CentOS nss Update
info-security done
But, I still do not see critical updates for CentOS 5 on vFense server. All updates are shown as optional.
Is there anything else could be done?