Vulnerabilities > CVE-2018-19476 - Incorrect Type Conversion or Cast vulnerability in multiple products

#
# (C) Tenable Network Security, Inc.
#
# The descriptive text and package checks in this plugin were  
# extracted from Red Hat Security Advisory RHSA-2019:0229 and 
# CentOS Errata and Security Advisory 2019:0229 respectively.
#

include("compat.inc");

if (description)
{
  script_id(122061);
  script_version("1.4");
  script_cvs_date("Date: 2019/12/31");

  script_cve_id("CVE-2018-16540", "CVE-2018-19475", "CVE-2018-19476", "CVE-2018-19477", "CVE-2019-6116");
  script_xref(name:"RHSA", value:"2019:0229");

  script_name(english:"CentOS 7 : ghostscript (CESA-2019:0229)");
  script_summary(english:"Checks rpm output for the updated packages");

  script_set_attribute(
    attribute:"synopsis", 
    value:"The remote CentOS 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 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 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) :

* ghostscript: use-after-free in copydevice handling (699661)
(CVE-2018-16540)

* ghostscript: access bypass in psi/zdevice2.c (700153)
(CVE-2018-19475)

* ghostscript: access bypass in psi/zicc.c (700169) (CVE-2018-19476)

* ghostscript: access bypass in psi/zfjbig2.c (700168)
(CVE-2018-19477)

* ghostscript: subroutines within pseudo-operators must themselves be
pseudo-operators (700317) (CVE-2019-6116)

For more details about the security issue(s), including the impact, a
CVSS score, and other related information, refer to the CVE page(s)
listed in the References section.

Red Hat would like to thank Tavis Ormandy (Google Project Zero) for
reporting CVE-2019-6116.

Bug Fix(es) :

* Previously, ghostscript-9.07-31.el7_6.1 introduced a regression
during the standard input reading, causing a '/invalidfileaccess in
--run--' error. With this update, the regression has been fixed and
the described error no longer occurs. (BZ#1665919)"
  );
  # https://lists.centos.org/pipermail/centos-announce/2019-February/023191.html
  script_set_attribute(
    attribute:"see_also",
    value:"http://www.nessus.org/u?437d1158"
  );
  script_set_attribute(
    attribute:"solution", 
    value:"Update the affected ghostscript packages."
  );
  script_set_cvss_base_vector("CVSS2#AV:N/AC:M/Au:N/C:P/I:P/A:P");
  script_set_cvss_temporal_vector("CVSS2#E:POC/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:P/RL:O/RC:C");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2018-16540");
  script_set_attribute(attribute:"exploitability_ease", value:"Exploits are available");
  script_set_attribute(attribute:"exploit_available", value:"true");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:centos:centos:ghostscript");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:centos:centos:ghostscript-cups");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:centos:centos:ghostscript-devel");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:centos:centos:ghostscript-doc");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:centos:centos:ghostscript-gtk");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:centos:centos:7");

  script_set_attribute(attribute:"vuln_publication_date", value:"2018/09/05");
  script_set_attribute(attribute:"patch_publication_date", value:"2019/02/09");
  script_set_attribute(attribute:"plugin_publication_date", value:"2019/02/11");
  script_set_attribute(attribute:"generated_plugin", value:"current");
  script_end_attributes();

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

  script_dependencies("ssh_get_info.nasl");
  script_require_keys("Host/local_checks_enabled", "Host/CentOS/release", "Host/CentOS/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/CentOS/release");
if (isnull(release) || "CentOS" >!< release) audit(AUDIT_OS_NOT, "CentOS");
os_ver = pregmatch(pattern: "CentOS(?: Linux)? release ([0-9]+)", string:release);
if (isnull(os_ver)) audit(AUDIT_UNKNOWN_APP_VER, "CentOS");
os_ver = os_ver[1];
if (! preg(pattern:"^7([^0-9]|$)", string:os_ver)) audit(AUDIT_OS_NOT, "CentOS 7.x", "CentOS " + os_ver);

if (!get_kb_item("Host/CentOS/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, "CentOS", cpu);


flag = 0;
if (rpm_check(release:"CentOS-7", cpu:"x86_64", reference:"ghostscript-9.07-31.el7_6.9")) flag++;
if (rpm_check(release:"CentOS-7", cpu:"x86_64", reference:"ghostscript-cups-9.07-31.el7_6.9")) flag++;
if (rpm_check(release:"CentOS-7", cpu:"x86_64", reference:"ghostscript-devel-9.07-31.el7_6.9")) flag++;
if (rpm_check(release:"CentOS-7", cpu:"x86_64", reference:"ghostscript-doc-9.07-31.el7_6.9")) flag++;
if (rpm_check(release:"CentOS-7", cpu:"x86_64", reference:"ghostscript-gtk-9.07-31.el7_6.9")) 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, "ghostscript / ghostscript-cups / ghostscript-devel / etc");
}