RHEL 7 : httpd (RHSA-2016:1422) (httpoxy)

2016-07-19T00:00:00
ID REDHAT-RHSA-2016-1422.NASL
Type nessus
Reporter This script is Copyright (C) 2016-2019 and is owned by Tenable, Inc. or an Affiliate thereof.
Modified 2020-04-02T00:00:00

Description

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

                                        
                                            #
# (C) Tenable Network Security, Inc.
#
# The descriptive text and package checks in this plugin were  
# extracted from Red Hat Security Advisory RHSA-2016:1422. The text 
# itself is copyright (C) Red Hat, Inc.
#

include("compat.inc");

if (description)
{
  script_id(92399);
  script_version("2.16");
  script_cvs_date("Date: 2019/10/24 15:35:41");

  script_cve_id("CVE-2016-5387");
  script_xref(name:"RHSA", value:"2016:1422");

  script_name(english:"RHEL 7 : httpd (RHSA-2016:1422) (httpoxy)");
  script_summary(english:"Checks the rpm output for the updated packages");

  script_set_attribute(
    attribute:"synopsis", 
    value:"The remote Red Hat host is missing one or more security updates."
  );
  script_set_attribute(
    attribute:"description", 
    value:
"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)"
  );
  script_set_attribute(
    attribute:"see_also",
    value:"https://access.redhat.com/errata/RHSA-2016:1422"
  );
  script_set_attribute(
    attribute:"see_also",
    value:"https://access.redhat.com/security/cve/cve-2016-5387"
  );
  script_set_attribute(attribute:"solution", value:"Update the affected packages.");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:H/Au:N/C:P/I:P/A:P");
  script_set_cvss_temporal_vector("CVSS2#E:U/RL:OF/RC:C");
  script_set_cvss3_base_vector("CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H");
  script_set_cvss3_temporal_vector("CVSS:3.0/E:U/RL:O/RC:C");
  script_set_attribute(attribute:"exploitability_ease", value:"No known exploits are available");
  script_set_attribute(attribute:"exploit_available", value:"false");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:redhat:enterprise_linux:httpd");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:redhat:enterprise_linux:httpd-debuginfo");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:redhat:enterprise_linux:httpd-devel");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:redhat:enterprise_linux:httpd-manual");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:redhat:enterprise_linux:httpd-tools");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:redhat:enterprise_linux:mod_ldap");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:redhat:enterprise_linux:mod_proxy_html");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:redhat:enterprise_linux:mod_session");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:redhat:enterprise_linux:mod_ssl");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:redhat:enterprise_linux:7");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:redhat:enterprise_linux:7.2");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:redhat:enterprise_linux:7.3");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:redhat:enterprise_linux:7.4");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:redhat:enterprise_linux:7.5");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:redhat:enterprise_linux:7.6");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:redhat:enterprise_linux:7.7");

  script_set_attribute(attribute:"vuln_publication_date", value:"2016/07/19");
  script_set_attribute(attribute:"patch_publication_date", value:"2016/07/18");
  script_set_attribute(attribute:"plugin_publication_date", value:"2016/07/19");
  script_set_attribute(attribute:"in_the_news", value:"true");
  script_set_attribute(attribute:"generated_plugin", value:"current");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_copyright(english:"This script is Copyright (C) 2016-2019 and is owned by Tenable, Inc. or an Affiliate thereof.");
  script_family(english:"Red Hat Local Security Checks");

  script_dependencies("ssh_get_info.nasl");
  script_require_keys("Host/local_checks_enabled", "Host/RedHat/release", "Host/RedHat/rpm-list", "Host/cpu");

  exit(0);
}


include("audit.inc");
include("global_settings.inc");
include("misc_func.inc");
include("rpm.inc");

if (!get_kb_item("Host/local_checks_enabled")) audit(AUDIT_LOCAL_CHECKS_NOT_ENABLED);
release = get_kb_item("Host/RedHat/release");
if (isnull(release) || "Red Hat" >!< release) audit(AUDIT_OS_NOT, "Red Hat");
os_ver = pregmatch(pattern: "Red Hat Enterprise Linux.*release ([0-9]+(\.[0-9]+)?)", string:release);
if (isnull(os_ver)) audit(AUDIT_UNKNOWN_APP_VER, "Red Hat");
os_ver = os_ver[1];
if (! preg(pattern:"^7([^0-9]|$)", string:os_ver)) audit(AUDIT_OS_NOT, "Red Hat 7.x", "Red Hat " + os_ver);

if (!get_kb_item("Host/RedHat/rpm-list")) audit(AUDIT_PACKAGE_LIST_MISSING);

cpu = get_kb_item("Host/cpu");
if (isnull(cpu)) audit(AUDIT_UNKNOWN_ARCH);
if ("x86_64" >!< cpu && cpu !~ "^i[3-6]86$" && "s390" >!< cpu) audit(AUDIT_LOCAL_CHECKS_NOT_IMPLEMENTED, "Red Hat", cpu);

yum_updateinfo = get_kb_item("Host/RedHat/yum-updateinfo");
if (!empty_or_null(yum_updateinfo)) 
{
  rhsa = "RHSA-2016:1422";
  yum_report = redhat_generate_yum_updateinfo_report(rhsa:rhsa);
  if (!empty_or_null(yum_report))
  {
    security_report_v4(
      port       : 0,
      severity   : SECURITY_WARNING,
      extra      : yum_report 
    );
    exit(0);
  }
  else
  {
    audit_message = "affected by Red Hat security advisory " + rhsa;
    audit(AUDIT_OS_NOT, audit_message);
  }
}
else
{
  flag = 0;
  if (rpm_check(release:"RHEL7", cpu:"s390x", reference:"httpd-2.4.6-40.el7_2.4")) flag++;

  if (rpm_check(release:"RHEL7", cpu:"x86_64", reference:"httpd-2.4.6-40.el7_2.4")) flag++;

  if (rpm_check(release:"RHEL7", cpu:"s390x", reference:"httpd-debuginfo-2.4.6-40.el7_2.4")) flag++;

  if (rpm_check(release:"RHEL7", cpu:"x86_64", reference:"httpd-debuginfo-2.4.6-40.el7_2.4")) flag++;

  if (rpm_check(release:"RHEL7", cpu:"s390x", reference:"httpd-devel-2.4.6-40.el7_2.4")) flag++;

  if (rpm_check(release:"RHEL7", cpu:"x86_64", reference:"httpd-devel-2.4.6-40.el7_2.4")) flag++;

  if (rpm_check(release:"RHEL7", reference:"httpd-manual-2.4.6-40.el7_2.4")) flag++;

  if (rpm_check(release:"RHEL7", cpu:"s390x", reference:"httpd-tools-2.4.6-40.el7_2.4")) flag++;

  if (rpm_check(release:"RHEL7", cpu:"x86_64", reference:"httpd-tools-2.4.6-40.el7_2.4")) flag++;

  if (rpm_check(release:"RHEL7", cpu:"s390x", reference:"mod_ldap-2.4.6-40.el7_2.4")) flag++;

  if (rpm_check(release:"RHEL7", cpu:"x86_64", reference:"mod_ldap-2.4.6-40.el7_2.4")) flag++;

  if (rpm_check(release:"RHEL7", cpu:"s390x", reference:"mod_proxy_html-2.4.6-40.el7_2.4")) flag++;

  if (rpm_check(release:"RHEL7", cpu:"x86_64", reference:"mod_proxy_html-2.4.6-40.el7_2.4")) flag++;

  if (rpm_check(release:"RHEL7", cpu:"s390x", reference:"mod_session-2.4.6-40.el7_2.4")) flag++;

  if (rpm_check(release:"RHEL7", cpu:"x86_64", reference:"mod_session-2.4.6-40.el7_2.4")) flag++;

  if (rpm_check(release:"RHEL7", cpu:"s390x", reference:"mod_ssl-2.4.6-40.el7_2.4")) flag++;

  if (rpm_check(release:"RHEL7", cpu:"x86_64", reference:"mod_ssl-2.4.6-40.el7_2.4")) flag++;


  if (flag)
  {
    security_report_v4(
      port       : 0,
      severity   : SECURITY_WARNING,
      extra      : rpm_report_get() + redhat_report_package_caveat()
    );
    exit(0);
  }
  else
  {
    tested = pkg_tests_get();
    if (tested) audit(AUDIT_PACKAGE_NOT_AFFECTED, tested);
    else audit(AUDIT_PACKAGE_NOT_INSTALLED, "httpd / httpd-debuginfo / httpd-devel / httpd-manual / httpd-tools / etc");
  }
}