Important: glibc

Issue Overview:

Fragmentation attacks possible when EDNS0 is enabled
The DNS stub resolver in the GNU C Library (aka glibc or libc6) before version 2.26, when EDNS support is enabled, will solicit large UDP responses from name servers, potentially simplifying off-path DNS spoofing attacks due to IP fragmentation.(CVE-2017-12132)

Buffer overflow in glob with GLOB_TILDE
The GNU C Library (aka glibc or libc6) before 2.27 contains an off-by-one error leading to a heap-based buffer overflow in the glob function in glob.c, related to the processing of home directories using the ~ operator followed by a long string.(CVE-2017-15670)

Denial of service in getnetbyname function
The nss_dns implementation of getnetbyname in GNU C Library (aka glibc) before 2.21, when the DNS backend in the Name Service Switch configuration is enabled, allows remote attackers to cause a denial of service (infinite loop) by sending a positive answer while a network name is being process.(CVE-2014-9402)

DNS resolver NULL pointer dereference with crafted record type
res_query in libresolv in glibc before 2.25 allows remote attackers to cause a denial of service (NULL pointer dereference and process crash).(CVE-2015-5180)

realpath() buffer underflow when getcwd() returns relative path allows privilege escalation
In glibc 2.26 and earlier there is confusion in the usage of getcwd() by realpath() which can be used to write before the destination buffer leading to a buffer underflow and potential code execution.(CVE-2018-1000001)

Buffer overflow during unescaping of user names with the ~ operator
The glob function in glob.c in the GNU C Library (aka glibc or libc6) before 2.27 contains a buffer overflow during unescaping of user names with the ~ operator.(CVE-2017-15804)

Affected Packages:

glibc

Issue Correction:
Run yum update glibc to update your system.

New Packages:

i686:  
    glibc-debuginfo-common-2.17-222.173.amzn1.i686  
    glibc-static-2.17-222.173.amzn1.i686  
    glibc-debuginfo-2.17-222.173.amzn1.i686  
    glibc-2.17-222.173.amzn1.i686  
    glibc-devel-2.17-222.173.amzn1.i686  
    glibc-utils-2.17-222.173.amzn1.i686  
    nscd-2.17-222.173.amzn1.i686  
    glibc-headers-2.17-222.173.amzn1.i686  
    glibc-common-2.17-222.173.amzn1.i686  
  
src:  
    glibc-2.17-222.173.amzn1.src  
  
x86_64:  
    nscd-2.17-222.173.amzn1.x86_64  
    glibc-common-2.17-222.173.amzn1.x86_64  
    glibc-utils-2.17-222.173.amzn1.x86_64  
    glibc-debuginfo-2.17-222.173.amzn1.x86_64  
    glibc-2.17-222.173.amzn1.x86_64  
    glibc-static-2.17-222.173.amzn1.x86_64  
    glibc-devel-2.17-222.173.amzn1.x86_64  
    glibc-headers-2.17-222.173.amzn1.x86_64  
    glibc-debuginfo-common-2.17-222.173.amzn1.x86_64  

Additional References

Red Hat: CVE-2014-9402, CVE-2015-5180, CVE-2017-12132, CVE-2017-15670, CVE-2017-15804, CVE-2018-1000001

Mitre: CVE-2014-9402, CVE-2015-5180, CVE-2017-12132, CVE-2017-15670, CVE-2017-15804, CVE-2018-1000001