$ yum upgrade
[...]
===============================================================================================================================================================
 Package                                Arch                            Version                                         Repository                        Size
===============================================================================================================================================================
Updating:
 glibc                                  x86_64                          2.17-55.el7_0.3                                 updates                          3.6 M
 glibc-common                           x86_64                          2.17-55.el7_0.3                                 updates                           11 M
 glibc-devel                            x86_64                          2.17-55.el7_0.3                                 updates                          1.0 M
 glibc-headers                          x86_64                          2.17-55.el7_0.3                                 updates                          650 k
 ntpdate                                x86_64                          4.2.6p5-19.el7.centos                           updates                           82 k

Transaction Summary
===============================================================================================================================================================
Upgrade  5 Packages

[...]