All, Please excuse any ignorance in this e-mail as I am not a RH/CentOS/Fedora user and may blunder my way through the correct terminology for my request. I'm tasked with reconstructing the CentOS version of the GlibC library for testing with gethostbyname(). My mission is to show that we are not affected by the latest exploit for the product we are shipping targeted for RHEL and CentOS. To do so, I want to equip gethostbyname() with additional code. My objective is to rebuild from source the EXACT version of GlibC for CentOS 6.6. Afterwards, I will make my changes in the code, rebuild and complete my testing. libc.so.6 reports: GNU C Library stable release version 2.12, by Roland McGrath et al. Copyright (C) 2010 Free Software Foundation, Inc. This is free software; see the source for copying conditions. There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. Compiled by GNU CC version 4.4.7 20120313 (Red Hat 4.4.7-11). Compiled on a Linux 2.6.32 system on 2015-01-27. Available extensions: The C stubs add-on version 2.1.2. crypt add-on version 2.1 by Michael Glad and others GNU Libidn by Simon Josefsson Native POSIX Threads Library by Ulrich Drepper et al BIND-8.2.3-T5B RT using linux kernel aio libc ABIs: UNIQUE IFUNC For bug reporting instructions, please see: <http://www.gnu.org/software/libc/bugs.html>. But, when looking through the source code for this version on the CentOS servers I only see: <http://vault.centos.org/6.6/updates/Source/SPackages/> [ ] glibc-2.12-1.149.el6_6.4.src.rpm 07-Jan-2015 22:45 15M [ ] glibc-2.12-1.149.el6_6.5.src.rpm 27-Jan-2015 23:13 15M Please point me to the correct source tarball, and all required patches so that I can reconstruct my loaded version of GlibC. A yum command is also acceptable. Thanks, Andy