RHEL 6 : ghostscript (RHSA-2018:3760)

#
# (C) Tenable Network Security, Inc.
#
# The descriptive text and package checks in this plugin were  
# extracted from Red Hat Security Advisory RHSA-2018:3760. The text 
# itself is copyright (C) Red Hat, Inc.
#

include("compat.inc");

if (description)
{
  script_id(119330);
  script_version("1.7");
  script_cvs_date("Date: 2019/10/24 15:35:46");

  script_cve_id("CVE-2018-16509");
  script_xref(name:"RHSA", value:"2018:3760");

  script_name(english:"RHEL 6 : ghostscript (RHSA-2018:3760)");
  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 ghostscript is now available for Red Hat Enterprise
Linux 6.

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 Ghostscript suite contains utilities for rendering PostScript and
PDF documents. Ghostscript translates PostScript code to common bitmap
formats so that the code can be displayed or printed.

Security Fix(es) :

* It was discovered that the ghostscript /invalidaccess checks fail
under certain conditions. An attacker could possibly exploit this to
bypass the -dSAFER protection and, for example, execute arbitrary
shell commands via a specially crafted PostScript document.
(CVE-2018-16509)

Red Hat would like to thank Tavis Ormandy (Google Project Zero) for
reporting this issue."
  );
  script_set_attribute(
    attribute:"see_also",
    value:"https://access.redhat.com/errata/RHSA-2018:3760"
  );
  script_set_attribute(
    attribute:"see_also",
    value:"https://access.redhat.com/security/cve/cve-2018-16509"
  );
  script_set_attribute(attribute:"solution", value:"Update the affected packages.");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:M/Au:N/C:C/I:C/A:C");
  script_set_cvss_temporal_vector("CVSS2#E:F/RL:OF/RC:C");
  script_set_cvss3_base_vector("CVSS:3.0/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H");
  script_set_cvss3_temporal_vector("CVSS:3.0/E:F/RL:O/RC:C");
  script_set_attribute(attribute:"exploitability_ease", value:"Exploits are available");
  script_set_attribute(attribute:"exploit_available", value:"true");
  script_set_attribute(attribute:"metasploit_name", value:'Ghostscript Failed Restore Command Execution');
  script_set_attribute(attribute:"exploit_framework_metasploit", value:"true");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:redhat:enterprise_linux:ghostscript");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:redhat:enterprise_linux:ghostscript-debuginfo");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:redhat:enterprise_linux:ghostscript-devel");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:redhat:enterprise_linux:ghostscript-doc");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:redhat:enterprise_linux:ghostscript-gtk");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:redhat:enterprise_linux:6");

  script_set_attribute(attribute:"vuln_publication_date", value:"2018/09/05");
  script_set_attribute(attribute:"patch_publication_date", value:"2018/12/03");
  script_set_attribute(attribute:"plugin_publication_date", value:"2018/12/04");
  script_set_attribute(attribute:"generated_plugin", value:"current");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_copyright(english:"This script is Copyright (C) 2018-2019 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-2018:3760";
  yum_report = redhat_generate_yum_updateinfo_report(rhsa:rhsa);
  if (!empty_or_null(yum_report))
  {
    security_report_v4(
      port       : 0,
      severity   : SECURITY_HOLE,
      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", reference:"ghostscript-8.70-24.el6_10.2")) flag++;
  if (rpm_check(release:"RHEL6", reference:"ghostscript-debuginfo-8.70-24.el6_10.2")) flag++;
  if (rpm_check(release:"RHEL6", reference:"ghostscript-devel-8.70-24.el6_10.2")) flag++;
  if (rpm_check(release:"RHEL6", cpu:"i686", reference:"ghostscript-doc-8.70-24.el6_10.2")) flag++;
  if (rpm_check(release:"RHEL6", cpu:"s390x", reference:"ghostscript-doc-8.70-24.el6_10.2")) flag++;
  if (rpm_check(release:"RHEL6", cpu:"x86_64", reference:"ghostscript-doc-8.70-24.el6_10.2")) flag++;
  if (rpm_check(release:"RHEL6", cpu:"i686", reference:"ghostscript-gtk-8.70-24.el6_10.2")) flag++;
  if (rpm_check(release:"RHEL6", cpu:"s390x", reference:"ghostscript-gtk-8.70-24.el6_10.2")) flag++;
  if (rpm_check(release:"RHEL6", cpu:"x86_64", reference:"ghostscript-gtk-8.70-24.el6_10.2")) flag++;

  if (flag)
  {
    security_report_v4(
      port       : 0,
      severity   : SECURITY_HOLE,
      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, "ghostscript / ghostscript-debuginfo / ghostscript-devel / etc");
  }
}