CentOS - Nov 2015 - [Slightly OT] - Looking for shadow-utils 4.2 SIG or SCL

Hi.

I'm looking to run unprivileged containers on CentOS 7 and this 
apparently requires shadow-utils 4.2 or higher [*0*].  CentOS 7 
currently has:

# rpm -q shadow-utils
shadow-utils-4.1.5.1-18.el7.x86_64

Is there a SIG or SCL that provides an updated package to facilitate my 
venture or am I left with the only choice of manually managing 
shadow-utils if I go the route of rpmbuild?

AK.

[*0*]: 
https://it-offshore.co.uk/linux/centos/29-centos-7-unprivileged-lxc-containers