Vulnerabilities > CVE-2016-4979 - Improper Access Control vulnerability in Apache Http Server 2.4.18/2.4.19/2.4.20

#
# (C) Tenable Network Security, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Gentoo Linux Security Advisory GLSA 201610-02.
#
# The advisory text is Copyright (C) 2001-2016 Gentoo Foundation, Inc.
# and licensed under the Creative Commons - Attribution / Share Alike 
# license. See http://creativecommons.org/licenses/by-sa/3.0/
#

include("compat.inc");

if (description)
{
  script_id(93903);
  script_version("$Revision: 2.5 $");
  script_cvs_date("$Date: 2017/01/16 16:05:33 $");

  script_cve_id("CVE-2014-3581", "CVE-2015-3183", "CVE-2016-1546", "CVE-2016-4979");
  script_xref(name:"GLSA", value:"201610-02");

  script_name(english:"GLSA-201610-02 : Apache: Multiple vulnerabilities");
  script_summary(english:"Checks for updated package(s) in /var/db/pkg");

  script_set_attribute(
    attribute:"synopsis", 
    value:
"The remote Gentoo host is missing one or more security-related
patches."
  );
  script_set_attribute(
    attribute:"description", 
    value:
"The remote host is affected by the vulnerability described in GLSA-201610-02
(Apache: Multiple vulnerabilities)

    Multiple vulnerabilities have been discovered in Apache HTTP Server.
      Please review the CVE identifiers referenced below for details.
  
Impact :

    Remote attackers could bypass intended access restrictions, conduct HTTP
      request smuggling attacks, or cause a Denial of Service condition.
  
Workaround :

    There is no known workaround at this time."
  );
  script_set_attribute(
    attribute:"see_also",
    value:"https://security.gentoo.org/glsa/201610-02"
  );
  script_set_attribute(
    attribute:"solution", 
    value:
"All Apache users should upgrade to the latest version:
      # emerge --sync
      # emerge --ask --oneshot --verbose '>=www-servers/apache-2.4.23'"
  );
  script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:N/I:N/A:P");
  script_set_cvss3_base_vector("CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:gentoo:linux:apache");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:gentoo:linux");

  script_set_attribute(attribute:"patch_publication_date", value:"2016/10/06");
  script_set_attribute(attribute:"plugin_publication_date", value:"2016/10/07");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_copyright(english:"This script is Copyright (C) 2016-2017 Tenable Network Security, Inc.");
  script_family(english:"Gentoo Local Security Checks");

  script_dependencies("ssh_get_info.nasl");
  script_require_keys("Host/local_checks_enabled", "Host/Gentoo/release", "Host/Gentoo/qpkg-list");

  exit(0);
}


include("audit.inc");
include("global_settings.inc");
include("qpkg.inc");

if (!get_kb_item("Host/local_checks_enabled")) audit(AUDIT_LOCAL_CHECKS_NOT_ENABLED);
if (!get_kb_item("Host/Gentoo/release")) audit(AUDIT_OS_NOT, "Gentoo");
if (!get_kb_item("Host/Gentoo/qpkg-list")) audit(AUDIT_PACKAGE_LIST_MISSING);


flag = 0;

if (qpkg_check(package:"www-servers/apache", unaffected:make_list("rge 2.2.31", "ge 2.4.23"), vulnerable:make_list("lt 2.4.23"))) flag++;

if (flag)
{
  if (report_verbosity > 0) security_warning(port:0, extra:qpkg_report_get());
  else security_warning(0);
  exit(0);
}
else
{
  tested = qpkg_tests_get();
  if (tested) audit(AUDIT_PACKAGE_NOT_AFFECTED, tested);
  else audit(AUDIT_PACKAGE_NOT_INSTALLED, "Apache");
}

#%NASL_MIN_LEVEL 80502
#
# (C) Tenable Network Security, Inc.
#
# The descriptive text and package checks in this plugin were  
# extracted from Fedora Security Advisory FEDORA-2016-e256a03791.
#

include("compat.inc");

if (description)
{
  script_id(92334);
  script_version("2.6");
  script_set_attribute(attribute:"plugin_modification_date", value:"2020/06/04");

  script_cve_id("CVE-2016-4979");
  script_xref(name:"FEDORA", value:"2016-e256a03791");

  script_name(english:"Fedora 23 : httpd (2016-e256a03791)");
  script_summary(english:"Checks rpm output for the updated package.");

  script_set_attribute(
    attribute:"synopsis", 
    value:"The remote Fedora host is missing a security update."
  );
  script_set_attribute(
    attribute:"description", 
    value:
"Security fix for CVE-2016-4979

Note that Tenable Network Security has extracted the preceding
description block directly from the Fedora update system website.
Tenable has attempted to automatically clean and format it as much as
possible without introducing additional issues."
  );
  script_set_attribute(
    attribute:"see_also",
    value:"https://bodhi.fedoraproject.org/updates/FEDORA-2016-e256a03791"
  );
  script_set_attribute(attribute:"solution", value:"Update the affected httpd package.");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:N/I:P/A:N");
  script_set_cvss3_base_vector("CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:fedoraproject:fedora:httpd");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:fedoraproject:fedora:23");

  script_set_attribute(attribute:"vuln_publication_date", value:"2016/07/06");
  script_set_attribute(attribute:"patch_publication_date", value:"2016/07/15");
  script_set_attribute(attribute:"plugin_publication_date", value:"2016/07/18");
  script_set_attribute(attribute:"generated_plugin", value:"current");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_copyright(english:"This script is Copyright (C) 2016-2020 and is owned by Tenable, Inc. or an Affiliate thereof.");
  script_family(english:"Fedora Local Security Checks");

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

  exit(0);
}


include("audit.inc");
include("global_settings.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) || "Fedora" >!< release) audit(AUDIT_OS_NOT, "Fedora");
os_ver = pregmatch(pattern: "Fedora.*release ([0-9]+)", string:release);
if (isnull(os_ver)) audit(AUDIT_UNKNOWN_APP_VER, "Fedora");
os_ver = os_ver[1];
if (! preg(pattern:"^23([^0-9]|$)", string:os_ver)) audit(AUDIT_OS_NOT, "Fedora 23", "Fedora " + 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$") audit(AUDIT_LOCAL_CHECKS_NOT_IMPLEMENTED, "Fedora", cpu);


flag = 0;
if (rpm_check(release:"FC23", reference:"httpd-2.4.23-3.fc23")) flag++;


if (flag)
{
  security_report_v4(
    port       : 0,
    severity   : SECURITY_WARNING,
    extra      : rpm_report_get()
  );
  exit(0);
}
else
{
  tested = pkg_tests_get();
  if (tested) audit(AUDIT_PACKAGE_NOT_AFFECTED, tested);
  else audit(AUDIT_PACKAGE_NOT_INSTALLED, "httpd");
}

#
# (C) Tenable Network Security, Inc.
#
# The descriptive text and package checks in this plugin were  
# extracted from the FreeBSD VuXML database :
#
# Copyright 2003-2019 Jacques Vidrine and contributors
#
# Redistribution and use in source (VuXML) and 'compiled' forms (SGML,
# HTML, PDF, PostScript, RTF and so forth) with or without modification,
# are permitted provided that the following conditions are met:
# 1. Redistributions of source code (VuXML) must retain the above
#    copyright notice, this list of conditions and the following
#    disclaimer as the first lines of this file unmodified.
# 2. Redistributions in compiled form (transformed to other DTDs,
#    published online in any format, converted to PDF, PostScript,
#    RTF and other formats) must reproduce the above copyright
#    notice, this list of conditions and the following disclaimer
#    in the documentation and/or other materials provided with the
#    distribution.
# 
# THIS DOCUMENTATION IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS "AS IS"
# AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
# THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
# PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS
# BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
# OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
# OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
# BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
# WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE
# OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS DOCUMENTATION,
# EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
#

include("compat.inc");

if (description)
{
  script_id(91949);
  script_version("2.7");
  script_cvs_date("Date: 2019/07/10 16:04:13");

  script_cve_id("CVE-2016-4979");

  script_name(english:"FreeBSD : apache24 -- X509 Client certificate based authentication can be bypassed when HTTP/2 is used (e9d1e040-42c9-11e6-9608-20cf30e32f6d)");
  script_summary(english:"Checks for updated package in pkg_info output");

  script_set_attribute(
    attribute:"synopsis", 
    value:"The remote FreeBSD host is missing a security-related update."
  );
  script_set_attribute(
    attribute:"description", 
    value:
"Apache Software Foundation reports :

The Apache HTTPD web server (from 2.4.18-2.4.20) did not validate a
X509 client certificate correctly when experimental module for the
HTTP/2 protocol is used to access a resource.

The net result is that a resource that should require a valid client
certificate in order to get access can be accessed without that
credential."
  );
  # http://mail-archives.apache.org/mod_mbox/httpd-announce/201607.mbox/CVE-2016-4979-68283
  script_set_attribute(
    attribute:"see_also",
    value:"http://www.nessus.org/u?089dcd60"
  );
  # https://vuxml.freebsd.org/freebsd/e9d1e040-42c9-11e6-9608-20cf30e32f6d.html
  script_set_attribute(
    attribute:"see_also",
    value:"http://www.nessus.org/u?9599c52d"
  );
  script_set_attribute(attribute:"solution", value:"Update the affected package.");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:N/I:P/A:N");
  script_set_cvss3_base_vector("CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:freebsd:freebsd:apache24");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:freebsd:freebsd");

  script_set_attribute(attribute:"vuln_publication_date", value:"2016/07/01");
  script_set_attribute(attribute:"patch_publication_date", value:"2016/07/05");
  script_set_attribute(attribute:"plugin_publication_date", value:"2016/07/06");
  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:"FreeBSD Local Security Checks");

  script_dependencies("ssh_get_info.nasl");
  script_require_keys("Host/local_checks_enabled", "Host/FreeBSD/release", "Host/FreeBSD/pkg_info");

  exit(0);
}


include("audit.inc");
include("freebsd_package.inc");


if (!get_kb_item("Host/local_checks_enabled")) audit(AUDIT_LOCAL_CHECKS_NOT_ENABLED);
if (!get_kb_item("Host/FreeBSD/release")) audit(AUDIT_OS_NOT, "FreeBSD");
if (!get_kb_item("Host/FreeBSD/pkg_info")) audit(AUDIT_PACKAGE_LIST_MISSING);


flag = 0;

if (pkg_test(save_report:TRUE, pkg:"apache24>=2.4.18<2.4.23")) flag++;

if (flag)
{
  if (report_verbosity > 0) security_warning(port:0, extra:pkg_report_get());
  else security_warning(0);
  exit(0);
}
else audit(AUDIT_HOST_NOT, "affected");

#
# (C) Tenable Network Security, Inc.
#

include("compat.inc");

if (description)
{
  script_id(92320);
  script_version("1.10");
  script_cvs_date("Date: 2019/11/14");

  script_cve_id("CVE-2016-4979");
  script_bugtraq_id(91566);

  script_name(english:"Apache 2.4.18 / 2.4.20 X.509 Certificate Authentication Bypass");
  script_summary(english:"Checks the version in the server response header.");

  script_set_attribute(attribute:"synopsis", value:
"The remote web server is affected by an authentication bypass
vulnerability.");
  script_set_attribute(attribute:"description", value:
"According to its banner, the version of Apache running on the remote
host is either 2.4.18 or 2.4.20. Additionally, HTTP/2 is enabled over
TLS or SSL. It is, therefore, affected by the an authentication bypass
vulnerability in the experimental module for the HTTP/2 protocol due
to a failure to correctly validate X.509 certificates, allowing access
to resources that otherwise would not be allowed. An unauthenticated,
remote attacker can exploit this to disclose potentially sensitive
information.");
  script_set_attribute(attribute:"see_also", value:"https://archive.apache.org/dist/httpd/CHANGES_2.4.23");
  script_set_attribute(attribute:"see_also", value:"https://httpd.apache.org/security/vulnerabilities_24.html");
  script_set_attribute(attribute:"see_also", value:"https://seclists.org/fulldisclosure/2016/Jul/11");
  script_set_attribute(attribute:"solution", value:
"Upgrade to Apache version 2.4.23 or later. Alternatively, as a
temporary workaround, HTTP/2 can be disabled by changing the
configuration by removing 'h2' and 'h2c' from the Protocols line(s)
in the configuration file.");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:N/I:P/A:N");
  script_set_cvss_temporal_vector("CVSS2#E:U/RL:OF/RC:C");
  script_set_cvss3_base_vector("CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N");
  script_set_cvss3_temporal_vector("CVSS:3.0/E:U/RL:O/RC:C");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2016-4979");

  script_set_attribute(attribute:"exploitability_ease", value:"No known exploits are available");
  script_set_attribute(attribute:"exploit_available", value:"false");

  script_set_attribute(attribute:"vuln_publication_date", value:"2016/07/05");
  script_set_attribute(attribute:"patch_publication_date", value:"2016/07/05");
  script_set_attribute(attribute:"plugin_publication_date", value:"2016/07/15");

  script_set_attribute(attribute:"plugin_type", value:"remote");
  script_set_attribute(attribute:"cpe", value:"cpe:/a:apache:http_server");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_family(english:"Web Servers");

  script_copyright(english:"This script is Copyright (C) 2016-2019 and is owned by Tenable, Inc. or an Affiliate thereof.");

  script_dependencies("alpn_protocol_enumeration.nasl", "apache_http_version.nasl");
  script_require_keys("installed_sw/Apache");
  script_require_ports("Services/www", 443);

  exit(0);
}

include("audit.inc");
include("global_settings.inc");
include("misc_func.inc");
include("http.inc");
include("install_func.inc");

get_install_count(app_name:"Apache", exit_if_zero:TRUE);
port = get_http_port(default:443);
install = get_single_install(app_name:"Apache", port:port, exit_if_unknown_ver:TRUE);

# see if http/2 is enabled (not h2c)
# this vuln has to do with x509 client cert verification
protos = get_kb_list("SSL/ALPN/"+port);
found = FALSE;

if (!isnull(protos))
{
  proto_list = make_list(protos);
  foreach proto (proto_list)
  {
    if (proto == 'h2')
    {
      found = TRUE;
      break;
    }
  }
}

if (!found) audit(AUDIT_NOT_DETECT, "An h2-enabled Apache web server", port);

# Check if we could get a version
version = get_kb_item_or_exit('www/apache/'+port+'/version', exit_code:1);
source = get_kb_item_or_exit('www/apache/'+port+'/source', exit_code:1);

# Ensure granularity
if (version =~ '^2(\\.4)?$') audit(AUDIT_VER_NOT_GRANULAR, 'Apache', port, version);

if (version == "2.4.18" || version == "2.4.20")
{
  report =
    '\n  Version source    : ' + source +
    '\n  Installed version : ' + version +
    '\n  Fixed version     : 2.4.23\n';

  security_report_v4(port:port, extra:report, severity:SECURITY_WARNING);
  exit(0);
}
else audit(AUDIT_LISTEN_NOT_VULN, "Apache", port, version);

#%NASL_MIN_LEVEL 80502
#
# (C) Tenable Network Security, Inc.
#
# The descriptive text and package checks in this plugin were  
# extracted from Fedora Security Advisory FEDORA-2016-c7288a5b36.
#

include("compat.inc");

if (description)
{
  script_id(92289);
  script_version("2.6");
  script_set_attribute(attribute:"plugin_modification_date", value:"2020/06/04");

  script_cve_id("CVE-2016-4979");
  script_xref(name:"FEDORA", value:"2016-c7288a5b36");

  script_name(english:"Fedora 24 : httpd (2016-c7288a5b36)");
  script_summary(english:"Checks rpm output for the updated package.");

  script_set_attribute(
    attribute:"synopsis", 
    value:"The remote Fedora host is missing a security update."
  );
  script_set_attribute(
    attribute:"description", 
    value:
"Security fix for CVE-2016-4979

Note that Tenable Network Security has extracted the preceding
description block directly from the Fedora update system website.
Tenable has attempted to automatically clean and format it as much as
possible without introducing additional issues."
  );
  script_set_attribute(
    attribute:"see_also",
    value:"https://bodhi.fedoraproject.org/updates/FEDORA-2016-c7288a5b36"
  );
  script_set_attribute(attribute:"solution", value:"Update the affected httpd package.");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:N/I:P/A:N");
  script_set_cvss3_base_vector("CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:fedoraproject:fedora:httpd");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:fedoraproject:fedora:24");

  script_set_attribute(attribute:"vuln_publication_date", value:"2016/07/06");
  script_set_attribute(attribute:"patch_publication_date", value:"2016/07/12");
  script_set_attribute(attribute:"plugin_publication_date", value:"2016/07/15");
  script_set_attribute(attribute:"generated_plugin", value:"current");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_copyright(english:"This script is Copyright (C) 2016-2020 and is owned by Tenable, Inc. or an Affiliate thereof.");
  script_family(english:"Fedora Local Security Checks");

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

  exit(0);
}


include("audit.inc");
include("global_settings.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) || "Fedora" >!< release) audit(AUDIT_OS_NOT, "Fedora");
os_ver = pregmatch(pattern: "Fedora.*release ([0-9]+)", string:release);
if (isnull(os_ver)) audit(AUDIT_UNKNOWN_APP_VER, "Fedora");
os_ver = os_ver[1];
if (! preg(pattern:"^24([^0-9]|$)", string:os_ver)) audit(AUDIT_OS_NOT, "Fedora 24", "Fedora " + 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$") audit(AUDIT_LOCAL_CHECKS_NOT_IMPLEMENTED, "Fedora", cpu);


flag = 0;
if (rpm_check(release:"FC24", reference:"httpd-2.4.23-3.fc24")) flag++;


if (flag)
{
  security_report_v4(
    port       : 0,
    severity   : SECURITY_WARNING,
    extra      : rpm_report_get()
  );
  exit(0);
}
else
{
  tested = pkg_tests_get();
  if (tested) audit(AUDIT_PACKAGE_NOT_AFFECTED, tested);
  else audit(AUDIT_PACKAGE_NOT_INSTALLED, "httpd");
}