The recent update to nss-softokn breaks rpm/yum updates in CentOS 6.
To restore functionality run these commands:
For 64-bit:
# wget http://mirror.centos.org/centos/6/updates/x86_64/Packages/nss-softokn-freebl-3.14.3-19.el6_6.x86_64.rpm
# rpm2cpio nss-softokn-freebl-3.14.3-19.el6_6.x86_64.rpm | cpio -idmv
# cd lib64
# cp libfreeblpriv3.* /lib64
# yum update
For 32-bit:
# wget http://mirror.centos.org/centos/6/updates/i386/Packages/nss-softokn-freebl-3.14.3-19.el6_6.i686.rpm
# rpm2cpio nss-softokn-freebl-3.14.3-19.el6_6.i686.rpm | cpio -idmv
# cd lib
# cp libfreeblpriv3.* /lib
# yum update
Good Job !!!