cbcvebase.
CVE-2016-5385
published 2016-07-19

CVE-2016-5385: 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…

PriorityP261high8.1CVSS 3.1
AVNACHPRNUINSUCHIHAH
EPSS
50.43%
98.8th percentile
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.

Affected

29 ranges· showing 25
VendorProductVersion rangeFixed in
amphpartax>= 0 < 1.0.41.0.4
amphpartax>= 2.0.0 < 2.0.42.0.4
bugsnagbugsnag-laravel>= 0 < 2.0.22.0.2
debiandebian_linux
drupalcore>= 8.0 < 8.1.78.1.7
drupaldrupal>= 8.0.0 < 8.1.78.1.7
fedoraprojectfedora
fedoraprojectfedora
guzzlehttpguzzle>= 4.0.0-rc2 < 4.2.44.2.4
guzzlehttpguzzle>= 5 < 5.3.15.3.1
guzzlehttpguzzle>= 6 < 6.2.16.2.1
hpstoreever_msl6480_tape_library_firmware<= 5.09
hpsystem_management_homepage<= 7.5.5.0
opensuseleap
oraclecommunications_user_data_repository
oraclecommunications_user_data_repository
oraclecommunications_user_data_repository
oracleenterprise_manager_ops_center
oracleenterprise_manager_ops_center
oraclelinux
oraclelinux
padraichumbug_get_contents>= 0 < 1.1.21.1.2
phpphp>= 5.5.0 < 5.5.385.5.38
phpphp>= 5.6.0 < 5.6.245.6.24
phpphp7.0.0 – 7.0.8

Detection & IOCsextracted from sources · hover to see the quote

  • Detect HTTP requests containing a 'Proxy' header, which PHP CGI maps to the HTTP_PROXY environment variable and may redirect outbound traffic to an attacker-controlled proxy.
  • In CGI deployments, the attacker-supplied Proxy header value enters the process environment and propagates to subprocesses via system()/exec(); monitor for unexpected HTTP_PROXY values in CGI process environments.
  • Under mod_php, the attack surface is limited: HTTP_PROXY enters $_SERVER but not $_ENV and does not leak to subprocesses; however getenv('HTTP_PROXY') or getenv('http_proxy') still returns the attacker-supplied value and may affect HTTP client libraries such as Guzzle.
  • Review PHP applications using the Guzzle HTTP client for exploitation; Guzzle reads HTTP_PROXY via getenv() and is a known affected library under the mod_php use case.
  • Patch reference: apply upstream PHP commit 98b9dfaec95e6f910f125ed172cdbd25abd006ec to remediate the HTTP_PROXY namespace conflict.
  • ·Under the most common Apache + mod_php deployment, HTTP_PROXY does not enter $_ENV and does not leak to subprocesses, making this vector less likely to be exploitable compared to CGI configurations.
  • ·PHP's getenv() case-sensitivity differs by SAPI: it is case-insensitive under mod_php (apache2handler) but case-sensitive under CGI (cgi-fcgi), affecting which call patterns are exploitable.
  • ·In CGI mode, libcurl (used by PHP's built-in curl functions) only honours the lowercase http_proxy environment variable, not HTTP_PROXY, limiting one specific sub-vector.
  • ·Red Hat Enterprise Linux 5 packages (php and php53) are marked 'Will not fix', meaning patched packages will not be provided for that platform.

CVSS provenance

nvdv3.18.1HIGHCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
nvdv2.05.1MEDIUMAV:N/AC:H/Au:N/C:P/I:P/A:P
osv9.8CRITICAL
vendor_ubuntu9.8CRITICAL
vendor_redhat8.1HIGH
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