The glibc packages provide the standard C libraries , POSIX thread libraries , standard math libraries , and the name service cache daemon used by multiple programs on the system. Without these libraries, the Linux system cannot function correctly. Security Fix: * A flaw was found in the way memory was being allocated on the stack for user space binaries. If heap and stack memory regions were adjacent to each other, an attacker could use this flaw to jump over the stack guard gap, cause controlled memory corruption on process stack or the adjacent memory region, and thus increase their privileges on the system. This is glibc-side mitigation which blocks processing of LD_LIBRARY_PATH for programs running in secure-execution mode and reduces the number of allocations performed by the processing of LD_AUDIT, LD_PRELOAD, and LD_HWCAP_MASK, making successful exploitation of this issue more difficult. Red Hat would like to thank Qualys Research Labs for reporting this issue.