RHEL 6 : httpd (RHSA-2017:1721)

#
# (C) Tenable Network Security, Inc.
#
# The descriptive text and package checks in this plugin were  
# extracted from Red Hat Security Advisory RHSA-2017:1721. The text 
# itself is copyright (C) Red Hat, Inc.
#

include("compat.inc");

if (description)
{
  script_id(101385);
  script_version("3.10");
  script_cvs_date("Date: 2019/10/24 15:35:43");

  script_cve_id("CVE-2016-8743");
  script_xref(name:"RHSA", value:"2017:1721");

  script_name(english:"RHEL 6 : httpd (RHSA-2017:1721)");
  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 6.

Red Hat Product Security has rated this update as having a security
impact of Moderate. 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 the HTTP parser in httpd incorrectly allowed
certain characters not permitted by the HTTP protocol specification to
appear unencoded in HTTP request headers. If httpd was used in
conjunction with a proxy or backend server that interpreted those
characters differently, a remote attacker could possibly use this flaw
to inject data into HTTP responses, resulting in proxy cache
poisoning. (CVE-2016-8743)

Note: The fix for the CVE-2016-8743 issue causes httpd to return '400
Bad Request' error to HTTP clients which do not strictly follow HTTP
protocol specification. A newly introduced configuration directive
'HttpProtocolOptions Unsafe' can be used to re-enable the old less
strict parsing. However, such setting also re-introduces the
CVE-2016-8743 issue.

Note: Administrators of Red Hat Satellite 5 and Red Hat Satellite
Proxy 5 systems should consult Red Hat Knowledgebase article 3013361
linked to in the Reference section before installing this update.

Bug Fix(es) :

* Previously, httpd was unable to correctly check a boundary of an
array, and in rare cases it attempted to access an element of an array
that was out of bounds. Consequently, httpd terminated unexpectedly
with a segmentation fault at proxy_util.c. With this update, bounds
checking has been fixed, and httpd no longer crashes. (BZ#1463354)"
  );
  script_set_attribute(
    attribute:"see_also",
    value:"https://access.redhat.com/articles/3013361"
  );
  script_set_attribute(
    attribute:"see_also",
    value:"https://access.redhat.com/errata/RHSA-2017:1721"
  );
  script_set_attribute(
    attribute:"see_also",
    value:"https://access.redhat.com/security/cve/cve-2016-8743"
  );
  script_set_attribute(attribute:"solution", value:"Update the affected packages.");
  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:"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_ssl");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:redhat:enterprise_linux:6");

  script_set_attribute(attribute:"vuln_publication_date", value:"2017/07/27");
  script_set_attribute(attribute:"patch_publication_date", value:"2017/07/11");
  script_set_attribute(attribute:"plugin_publication_date", value:"2017/07/12");
  script_set_attribute(attribute:"generated_plugin", value:"current");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_copyright(english:"This script is Copyright (C) 2017-2019 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:"^6([^0-9]|$)", string:os_ver)) audit(AUDIT_OS_NOT, "Red Hat 6.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-2017:1721";
  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:"RHEL6", cpu:"i686", reference:"httpd-2.2.15-60.el6_9.4")) flag++;
  if (rpm_check(release:"RHEL6", cpu:"s390x", reference:"httpd-2.2.15-60.el6_9.4")) flag++;
  if (rpm_check(release:"RHEL6", cpu:"x86_64", reference:"httpd-2.2.15-60.el6_9.4")) flag++;
  if (rpm_check(release:"RHEL6", reference:"httpd-debuginfo-2.2.15-60.el6_9.4")) flag++;
  if (rpm_check(release:"RHEL6", reference:"httpd-devel-2.2.15-60.el6_9.4")) flag++;
  if (rpm_check(release:"RHEL6", reference:"httpd-manual-2.2.15-60.el6_9.4")) flag++;
  if (rpm_check(release:"RHEL6", cpu:"i686", reference:"httpd-tools-2.2.15-60.el6_9.4")) flag++;
  if (rpm_check(release:"RHEL6", cpu:"s390x", reference:"httpd-tools-2.2.15-60.el6_9.4")) flag++;
  if (rpm_check(release:"RHEL6", cpu:"x86_64", reference:"httpd-tools-2.2.15-60.el6_9.4")) flag++;
  if (rpm_check(release:"RHEL6", cpu:"i686", reference:"mod_ssl-2.2.15-60.el6_9.4")) flag++;
  if (rpm_check(release:"RHEL6", cpu:"s390x", reference:"mod_ssl-2.2.15-60.el6_9.4")) flag++;
  if (rpm_check(release:"RHEL6", cpu:"x86_64", reference:"mod_ssl-2.2.15-60.el6_9.4")) 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");
  }
}