Bug 1353755 (CVE-2016-5387, httpoxy)

Summary:	CVE-2016-5387 Apache HTTPD: sets environmental variable based on user supplied Proxy request header
Product:	[Other] Security Response	Reporter:	Kurt Seifried <kseifried>
Component:	vulnerability	Assignee:	Red Hat Product Security <security-response-team>
Status:	CLOSED ERRATA	QA Contact:
Severity:	high	Docs Contact:
Priority:	high
Version:	unspecified	CC:	anemec, bbaranow, bmaxwell, cdewolf, chazlett, crrobins, csutherl, dandread, darran.lofthouse, dosoudil, fnasser, hhorak, huwang, jason.greene, jawilson, jboss-set, jclere, jdoyle, jkaluza, jorton, jshepherd, kseifried, lgao, mbabacek, mfrodl, mhatanak, mjc, mturk, myarboro, optak, pahan, pgier, psakar, pslavice, rnetuka, rsawhill, rsvoboda, sardella, security-response-team, sreber, twalsh, vtunka, weli
Target Milestone:	---	Keywords:	Security
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:	httpd 2.4.24, httpd 2.2.32	Doc Type:	If docs needed, set a value
Doc Text:	It was discovered that httpd used the value of the Proxy header from HTTP requests to initialize the HTTP_PROXY environment variable for CGI scripts, which in turn was incorrectly used by certain HTTP client implementations to configure the proxy for outgoing HTTP requests. A remote attacker could possibly use this flaw to redirect HTTP requests performed by a CGI script to an attacker-controlled proxy via a malicious HTTP request.	Story Points:	---
Clone Of:		Environment:
Last Closed:	2016-10-13 08:59:55 UTC	Type:	---
Regression:	---	Mount Type:	---
Documentation:	---	CRM:
Verified Versions:		Category:	---
oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:
Bug Depends On:	1360529, 1354577, 1354578, 1354579, 1354580, 1354581, 1354582, 1357597, 1358118, 1360356, 1360357
Bug Blocks:	1353762, 1358998

Description Kurt Seifried 2016-07-07 22:52:38 UTC

Dominic Scheirlinck of VendHQ reports:

Many software projects and vendors have implemented support for the “Proxy” request header in their respective CGI implementations and languages by creating the “HTTP_PROXY” environmental variable based on the header value. When this variable is used (in many cases automatically by various HTTP client libraries) any outgoing requests generated in turn from the attackers original request can be redirected to an attacker controlled proxy. This allows attackers to view potentially sensitive information, reply with malformed data, or to hold connections open causing a potential denial of service. 

The Apache HTTPD server sets various environmental variables based on headers that can then be used in CGI scripts (e.g. via mod_cgi). If passed a “Proxy” header in the request Apache will automatically populate the HTTP_PROXY environmental variable with whatever user supplied value is present.

Comment 1 Kurt Seifried 2016-07-07 22:52:42 UTC

Acknowledgments:

Name: Scott Geary (VendHQ)

Comment 12 Tomas Hoger 2016-07-18 14:30:20 UTC

Detailed write-up from the original reporter:

https://httpoxy.org/

Advisory from the Apache Software Foundation (which covers httpd, and also Tomcat and Traffic Server):

https://www.apache.org/security/asf-httpoxy-response.txt

ASF plans to address this issue in httpd versions 2.4.24 and 2.2.32.

Comment 13 Tomas Hoger 2016-07-18 14:30:57 UTC

External References:

https://access.redhat.com/security/vulnerabilities/httpoxy
https://httpoxy.org/
https://www.apache.org/security/asf-httpoxy-response.txt

Comment 14 Stefan Cornelius 2016-07-18 15:31:38 UTC

Created httpd tracking bugs for this issue:

Affects: fedora-all [bug 1357597]

Comment 15 errata-xmlrpc 2016-07-18 15:33:31 UTC

This issue has been addressed in the following products:

  Red Hat Software Collections for Red Hat Enterprise Linux 7.2 EUS
  Red Hat Software Collections for Red Hat Enterprise Linux 7.1 EUS
  Red Hat Software Collections for Red Hat Enterprise Linux 7
  Red Hat Software Collections for Red Hat Enterprise Linux 6.7 EUS
  Red Hat Software Collections for Red Hat Enterprise Linux 6.6 EUS
  Red Hat Software Collections for Red Hat Enterprise Linux 6

Via RHSA-2016:1420 https://access.redhat.com/errata/RHSA-2016:1420

Comment 16 errata-xmlrpc 2016-07-18 16:50:42 UTC

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 7

Via RHSA-2016:1422 https://access.redhat.com/errata/RHSA-2016:1422

Comment 17 errata-xmlrpc 2016-07-18 17:29:18 UTC

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 6
  Red Hat Enterprise Linux 5

Via RHSA-2016:1421 https://access.redhat.com/errata/RHSA-2016:1421

Comment 25 Fedora Update System 2016-07-22 15:58:56 UTC

httpd-2.4.23-4.fc24 has been pushed to the Fedora 24 stable repository. If problems still persist, please make note of it in this bug report.

Comment 29 Fedora Update System 2016-07-27 20:52:14 UTC

httpd-2.4.23-4.fc23 has been pushed to the Fedora 23 stable repository. If problems still persist, please make note of it in this bug report.

Comment 33 errata-xmlrpc 2016-08-17 18:02:14 UTC

This issue has been addressed in the following products:

  Red Hat JBoss Web Server 3.0.3

Via RHSA-2016:1624 https://rhn.redhat.com/errata/RHSA-2016-1624.html

Comment 35 errata-xmlrpc 2016-08-17 19:37:03 UTC

This issue has been addressed in the following products:

  Red Hat JBoss Core Services Apache HTTP 2.4.6

Via RHSA-2016:1625 https://rhn.redhat.com/errata/RHSA-2016-1625.html

Comment 36 errata-xmlrpc 2016-08-18 18:22:32 UTC

This issue has been addressed in the following products:

  Red Hat JBoss Web Server 3 for RHEL 7

Via RHSA-2016:1635 https://access.redhat.com/errata/RHSA-2016:1635

Comment 37 errata-xmlrpc 2016-08-18 19:01:05 UTC

This issue has been addressed in the following products:

  Red Hat JBoss Web Server 3 for RHEL 6

Via RHSA-2016:1636 https://access.redhat.com/errata/RHSA-2016:1636

Comment 38 errata-xmlrpc 2016-08-22 18:10:31 UTC

This issue has been addressed in the following products:

  Red Hat JBoss Web Server 2.1.1

Via RHSA-2016:1650 https://rhn.redhat.com/errata/RHSA-2016-1650.html

Comment 39 errata-xmlrpc 2016-08-22 18:11:46 UTC

This issue has been addressed in the following products:

  Red Hat JBoss Enterprise Web Server 2 for RHEL 6

Via RHSA-2016:1649 https://rhn.redhat.com/errata/RHSA-2016-1649.html

Comment 40 errata-xmlrpc 2016-08-22 18:12:38 UTC

This issue has been addressed in the following products:

  Red Hat JBoss Enterprise Web Server 2 for RHEL 7

Via RHSA-2016:1648 https://rhn.redhat.com/errata/RHSA-2016-1648.html

Comment 41 errata-xmlrpc 2016-09-12 16:59:08 UTC

This issue has been addressed in the following products:

  JBoss Core Services on RHEL 7
  JBoss Core Services on RHEL 6

Via RHSA-2016:1851 https://access.redhat.com/errata/RHSA-2016:1851