Apache Tomcat 7.x through 7.0.70 and 8.x through 8.5.4, when the CGI Servlet is enabled, follows RFC 3875 section 4.1.18 and therefore does not protect applications from the presence of untrusted client data in the HTTP_PROXY environment variable, which might allow remote attackers to redirect an application’s outbound HTTP traffic to an arbitrary proxy server via a crafted Proxy header in an HTTP request, aka an “httpoxy” issue. NOTE: the vendor states “A mitigation is planned for future releases of Tomcat, tracked as CVE-2016-5388”; in other words, this is not a CVE ID for a vulnerability.
access.redhat.com/errata/RHSA-2016:1624
access.redhat.com/errata/RHSA-2016:1635
access.redhat.com/errata/RHSA-2016:1636
access.redhat.com/errata/RHSA-2016:2045
access.redhat.com/errata/RHSA-2016:2046
access.redhat.com/security/cve/CVE-2016-5388
bugzilla.redhat.com/show_bug.cgi?id=1353809
github.com/apache/tomcat
github.com/apache/tomcat/commit/1b91e91194a095ea922f96d1dccddf6fbc446e54
github.com/apache/tomcat/commit/880250877b0643956435282afb9c111450cfff4c
github.com/apache/tomcat/commit/fb3569fbb9a2f55459aa8e1e22bc35a737e66329
h20566.www2.hpe.com/hpsc/doc/public/display?docLocale=en_US&docId=emr_na-hpesbhf03770en_us
h20566.www2.hpe.com/portal/site/hpsc/public/kb/docDisplay?docId=emr_na-c05320149
h20566.www2.hpe.com/portal/site/hpsc/public/kb/docDisplay?docId=emr_na-c05324759
h20566.www2.hpe.com/portal/site/hpsc/public/kb/docDisplay?docId=emr_na-c05390722
lists.apache.org/thread.html/053d9ce4d579b02203db18545fee5e33f35f2932885459b74d1e4272%40%3Cissues.activemq.apache.org%3E
lists.apache.org/thread.html/053d9ce4d579b02203db18545fee5e33f35f2932885459b74d1e4272@%3Cissues.activemq.apache.org%3E
lists.apache.org/thread.html/6b414817c2b0bf351138911c8c922ec5dd577ebc0b9a7f42d705752d%40%3Cissues.activemq.apache.org%3E
lists.apache.org/thread.html/6b414817c2b0bf351138911c8c922ec5dd577ebc0b9a7f42d705752d@%3Cissues.activemq.apache.org%3E
lists.apache.org/thread.html/6d3d34adcf3dfc48e36342aa1f18ce3c20bb8e4c458a97508d5bfed1%40%3Cissues.activemq.apache.org%3E
lists.apache.org/thread.html/6d3d34adcf3dfc48e36342aa1f18ce3c20bb8e4c458a97508d5bfed1@%3Cissues.activemq.apache.org%3E
lists.apache.org/thread.html/r2853582063cfd9e7fbae1e029ae004e6a83482ae9b70a698996353dd%40%3Cusers.tomcat.apache.org%3E
lists.apache.org/thread.html/r2853582063cfd9e7fbae1e029ae004e6a83482ae9b70a698996353dd@%3Cusers.tomcat.apache.org%3E
lists.apache.org/thread.html/rc6b2147532416cc736e68a32678d3947b7053c3085cf43a9874fd102%40%3Cusers.tomcat.apache.org%3E
lists.apache.org/thread.html/rc6b2147532416cc736e68a32678d3947b7053c3085cf43a9874fd102@%3Cusers.tomcat.apache.org%3E
lists.apache.org/thread.html/rf21b368769ae70de4dee840a3228721ae442f1d51ad8742003aefe39%40%3Cusers.tomcat.apache.org%3E
lists.apache.org/thread.html/rf21b368769ae70de4dee840a3228721ae442f1d51ad8742003aefe39@%3Cusers.tomcat.apache.org%3E
lists.debian.org/debian-lts-announce/2019/08/msg00015.html
lists.opensuse.org/opensuse-updates/2016-09/msg00025.html
nvd.nist.gov/vuln/detail/CVE-2016-5388
rhn.redhat.com/errata/RHSA-2016-1624.html
rhn.redhat.com/errata/RHSA-2016-2045.html
rhn.redhat.com/errata/RHSA-2016-2046.html
tomcat.apache.org/tomcat-7.0-doc/changelog.html
www.apache.org/security/asf-httpoxy-response.txt
www.kb.cert.org/vuls/id/797896