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 discovered that the nss_files backend for the Name Service Switch in glibc would return incorrect data to applications or corrupt the heap (depending on adjacent heap contents) in certain cases. A local attacker could potentially use this flaw to escalate their privileges. (CVE-2015-5277) This issue was discovered by Sumit Bose and Lukáš Slebodník of Red Hat. All glibc users are advised to upgrade to these updated packages, which contain a backported patch to correct this issue.