RHEL 6 / 7 : glibc (RHSA-2017:1479) (Stack Clash)
High Nessus Plugin ID 100890
SynopsisThe remote Red Hat host is missing one or more security updates.
DescriptionAn update for glibc is now available for Red Hat Enterprise Linux 5 Extended Lifecycle Support, Red Hat Enterprise Linux 5.9 Long Life, Red Hat Enterprise Linux 6.2 Advanced Update Support, Red Hat Enterprise Linux 6.4 Advanced Update Support, Red Hat Enterprise Linux 6.5 Advanced Update Support, Red Hat Enterprise Linux 6.5 Telco Extended Update Support, Red Hat Enterprise Linux 6.6 Advanced Update Support, Red Hat Enterprise Linux 6.6 Telco Extended Update Support, Red Hat Enterprise Linux 6.7 Extended Update Support, and Red Hat Enterprise Linux 7.2 Extended Update Support.
Red Hat Product Security has rated this update as having a security impact of Important. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link(s) in the References section.
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.
SolutionUpdate the affected packages.