libmcrypt from home:non7top:epel7 project
Select Your Operating System
Add repository and install manually
For CentOS 7 run the following as root:
cd /etc/yum.repos.d/ wget https://download.opensuse.org/repositories/home:non7top:epel7/CentOS_7/home:non7top:epel7.repo yum install libmcrypt