Red Hat Security Advisory 2015-0863-01 – The glibc packages provide the standard C libraries, POSIX thread libraries, standard math libraries, and the Name Server Caching Daemon used by multiple programs on the system. Without these libraries, the Linux system cannot function correctly. A buffer overflow flaw was found in the way glibc’s gethostbyname_r() and other related functions computed the size of a buffer when passed a misaligned buffer as input. An attacker able to make an application call any of these functions with a misaligned buffer could use this flaw to crash the application or, potentially, execute arbitrary code with the permissions of the user running the application.