PHP through 7.0.8 does not attempt to address RFC 3875 section 4.1.18 namespace conflicts 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, as demonstrated by (1) an application that makes a getenv('HTTP_PROXY') call or (2) a CGI configuration of PHP, aka an "httpoxy" issue.
https://bugzilla.redhat.com/show_bug.cgi?id=1353794
http://www.kb.cert.org/vuls/id/797896
http://www.oracle.com/technetwork/topics/security/linuxbulletinjul2016-3090544.html
https://h20566.www2.hpe.com/portal/site/hpsc/public/kb/docDisplay?docId=emr_na-c05320149
https://h20566.www2.hpe.com/portal/site/hpsc/public/kb/docDisplay?docId=emr_na-c05333297
http://lists.opensuse.org/opensuse-updates/2016-08/msg00003.html
http://www.securityfocus.com/bid/91821
http://rhn.redhat.com/errata/RHSA-2016-1611.html
http://rhn.redhat.com/errata/RHSA-2016-1612.html
http://rhn.redhat.com/errata/RHSA-2016-1613.html
http://rhn.redhat.com/errata/RHSA-2016-1610.html
http://rhn.redhat.com/errata/RHSA-2016-1609.html
https://h20566.www2.hpe.com/portal/site/hpsc/public/kb/docDisplay?docId=emr_na-c05390722
https://www.drupal.org/SA-CORE-2016-003
https://github.com/guzzle/guzzle/releases/tag/6.2.1
https://security.gentoo.org/glsa/201611-22
http://www.oracle.com/technetwork/security-advisory/cpujul2017-3236622.html
https://h20566.www2.hpe.com/hpsc/doc/public/display?docLocale=en_US&docId=emr_na-hpesbhf03770en_us
http://www.securitytracker.com/id/1036335
http://www.debian.org/security/2016/dsa-3631
http://www.oracle.com/technetwork/security-advisory/cpujan2018-3236628.html
Source: MITRE
Published: 2016-07-19
Updated: 2022-08-29
Type: CWE-601
Base Score: 5.1
Vector: AV:N/AC:H/Au:N/C:P/I:P/A:P
Impact Score: 6.4
Exploitability Score: 4.9
Severity: MEDIUM
Base Score: 8.1
Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
Impact Score: 5.9
Exploitability Score: 2.2
Severity: HIGH