Important CentOS httpd Security Update


httpd-2.4.6-40.el7.centos.4.src.rpm, httpd-2.4.6-40.el7.centos.4.x86_64.rpm, httpd-devel-2.4.6-40.el7.centos.4.x86_64.rpm, httpd-manual-2.4.6-40.el7.centos.4.noarch.rpm, httpd-tools-2.4.6-40.el7.centos.4.x86_64.rpm, mod_ldap-2.4.6-40.el7.centos.4.x86_64.rpm, mod_proxy_html-2.4.6-40.el7.centos.4.x86_64.rpm, mod_session-2.4.6-40.el7.centos.4.x86_64.rpm, mod_ssl-2.4.6-40.el7.centos.4.x86_64.rpm,
2018-01-18 11:12
2017-07-27 19:11
2017-04-01 19:10
2017-01-05 20:14


An update for httpd is now available for Red Hat Enterprise Linux 7.

Red Hat Product Security has rated this update as having a security impact of Important. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link(s) in the References section.

The httpd packages provide the Apache HTTP Server, a powerful, efficient, and extensible web server.

Security Fix(es):

* 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. (CVE-2016-5387)

Note: After this update, httpd will no longer pass the value of the Proxy request header to scripts via the HTTP_PROXY environment variable.

Red Hat would like to thank Scott Geary (VendHQ) for reporting this issue.

Bug Fix(es):

* In a caching proxy configuration, the mod_cache module would treat content as stale if the Expires header changed when refreshing a cached response. As a consequence, an origin server returning content without a fixed Expires header would not be treated as cacheable. The mod_cache module has been fixed to ignore changes in the Expires header when refreshing content. As a result, such content is now cacheable, improving performance and reducing load at the origin server. (BZ#1347648)

* The HTTP status code 451 "Unavailable For Legal Reasons" was not usable in the httpd configuration. As a consequence, modules such as mod_rewrite could not be configured to return a 451 error if required for legal purposes. The 451 status code has been added to the list of available error codes, and modules can now be configured to return a 451 error if required. (BZ#1353269)
Please see

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Affected package information

Release Package Patched in
7 httpd httpd-2.4.6-40.el7.centos.4.src.rpm
httpd httpd-2.4.6-40.el7.centos.4.x86_64.rpm
httpd-devel httpd-devel-2.4.6-40.el7.centos.4.x86_64.rpm
httpd-manual httpd-manual-2.4.6-40.el7.centos.4.noarch.rpm
httpd-tools httpd-tools-2.4.6-40.el7.centos.4.x86_64.rpm
mod_ldap mod_ldap-2.4.6-40.el7.centos.4.x86_64.rpm
mod_proxy_html mod_proxy_html-2.4.6-40.el7.centos.4.x86_64.rpm
mod_session mod_session-2.4.6-40.el7.centos.4.x86_64.rpm
mod_ssl mod_ssl-2.4.6-40.el7.centos.4.x86_64.rpm