...
[root@hp8300 me]# ldd --version
ldd (GNU libc) 2.17
[root@hp8300 me]# yum list glibc
. . .
glibc.i686 2.17-196.el7_4.2 @updates
glibc.x86_64 2.17-196.el7_4.2 @updates
Sadly did not work:
cd /tmp
wget http://ftp.gnu.org/gnu/glibc/glibc-2.18.tar.gz
tar -xvzf glibc-2.18.tar.gz
cd glibc-2.18/
mkdir glibc-build
cd glibc-build/
../configure --disable-sanity-checks
make
make install