It was reported  that scanf and related functions are crashing due to a bug  in glibc.
This issue affects the version of glibc package as shipped with Red Hat Enterprise Linux 5 and 6. Red Hat Product Security has rated this issue as having Low security impact. A future update in Red Hat Enterprise Linux 6 may address this issue. This issue did not affect the versions of glibc as shipped with Red Hat Enterprise Linux 7.
Red Hat Enterprise Linux 5 is now in Extended Life Cycle phase of the support and maintenance life cycle. This issue is not currently planned to be addressed in future updates.