The glibc packages provide the standard C libraries (libc), POSIX thread libraries (libpthread), standard math libraries (libm), and the Name Server Caching Daemon (nscd) used by multiple programs on the system. Without these libraries, the Linux system cannot function correctly.
It was found that the wordexp() function would perform command substitution even when the WRDE_NOCMD flag was specified. An attacker able to provide specially crafted input to an application using the wordexp() function, and not sanitizing the input correctly, could potentially use this flaw to execute arbitrary commands with the credentials of the user running that application. (CVE-2014-7817)
This issue was discovered by Tim Waugh of the Red Hat Developer Experience Team.
This update also fixes the following bug:
All glibc users are advised to upgrade to these updated packages, which contain backported patches to correct these issues.