The expansion of '\h' in the prompt string in bash 4.3 allows remote authenticated users to execute arbitrary code via shell metacharacters placed in 'hostname' of a machine.
https://security.gentoo.org/glsa/201612-39
https://bugzilla.redhat.com/show_bug.cgi?id=1377613
https://access.redhat.com/errata/RHSA-2017:1931
http://www.securityfocus.com/bid/92999
http://www.openwall.com/lists/oss-security/2016/10/10/4
http://www.openwall.com/lists/oss-security/2016/10/10/3
http://www.openwall.com/lists/oss-security/2016/10/07/6
http://www.openwall.com/lists/oss-security/2016/09/29/27
http://www.openwall.com/lists/oss-security/2016/09/27/9
http://www.openwall.com/lists/oss-security/2016/09/20/1
http://www.openwall.com/lists/oss-security/2016/09/19/7
http://www.openwall.com/lists/oss-security/2016/09/18/11
http://www.openwall.com/lists/oss-security/2016/09/16/8