(RHSA-2017:1479) Important: glibc security update

The glibc packages provide the standard C libraries (libc), POSIX thread
libraries (libpthread), standard math libraries (libm), and the name service
cache daemon (nscd) used by multiple programs on the system. Without these
libraries, the Linux system cannot function correctly.

Security Fix(es):

• A flaw was found in the way memory was being allocated on the stack for user
  space binaries. If heap (or different memory region) 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. (CVE-2017-1000366)

Red Hat would like to thank Qualys Research Labs for reporting this issue.