Amazon Linux AMI : ghostscript (ALAS-2017-837)

#
# (C) Tenable Network Security, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Amazon Linux AMI Security Advisory ALAS-2017-837.
#

include('compat.inc');

if (description)
{
  script_id(100638);
  script_version("3.7");
  script_set_attribute(attribute:"plugin_modification_date", value:"2025/12/17");

  script_cve_id("CVE-2017-8291");
  script_xref(name:"ALAS", value:"2017-837");
  script_xref(name:"RHSA", value:"2017:1230");
  script_xref(name:"CISA-KNOWN-EXPLOITED", value:"2022/06/14");

  script_name(english:"Amazon Linux AMI : ghostscript (ALAS-2017-837)");

  script_set_attribute(attribute:"synopsis", value:
"The remote Amazon Linux AMI host is missing a security update.");
  script_set_attribute(attribute:"description", value:
"It was found that ghostscript did not properly validate the parameters
passed

to the .rsdparams and .eqproc functions. During its execution, a
specially

crafted PostScript document could execute code in the context of the
ghostscript

process, bypassing the -dSAFER protection. (CVE-2017-8291)");
  script_set_attribute(attribute:"see_also", value:"https://alas.aws.amazon.com/ALAS-2017-837.html");
  script_set_attribute(attribute:"solution", value:
"Run 'yum update ghostscript' to update your system.");
  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:H/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:H/RL:O/RC:C");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2017-8291");

  script_set_attribute(attribute:"exploitability_ease", value:"Exploits are available");
  script_set_attribute(attribute:"exploit_available", value:"true");
  script_set_attribute(attribute:"exploited_by_malware", value:"true");
  script_set_attribute(attribute:"metasploit_name", value:'Ghostscript Type Confusion Arbitrary Command Execution');
  script_set_attribute(attribute:"exploit_framework_metasploit", value:"true");

  script_set_attribute(attribute:"patch_publication_date", value:"2017/06/06");
  script_set_attribute(attribute:"plugin_publication_date", value:"2017/06/07");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:ghostscript");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:ghostscript-debuginfo");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:ghostscript-devel");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:ghostscript-doc");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:amazon:linux");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_family(english:"Amazon Linux Local Security Checks");

  script_copyright(english:"This script is Copyright (C) 2017-2025 and is owned by Tenable, Inc. or an Affiliate thereof.");

  script_dependencies("ssh_get_info.nasl");
  script_require_keys("Host/local_checks_enabled", "Host/AmazonLinux/release", "Host/AmazonLinux/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/AmazonLinux/release");
if (isnull(release) || !strlen(release)) audit(AUDIT_OS_NOT, "Amazon Linux");
os_ver = pregmatch(pattern: "^AL(A|\d)", string:release);
if (isnull(os_ver)) audit(AUDIT_UNKNOWN_APP_VER, "Amazon Linux");
os_ver = os_ver[1];
if (os_ver != "A")
{
  if (os_ver == 'A') os_ver = 'AMI';
  audit(AUDIT_OS_NOT, "Amazon Linux AMI", "Amazon Linux " + os_ver);
}

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


flag = 0;
if (rpm_check(release:"ALA", reference:"ghostscript-8.70-23.25.amzn1")) flag++;
if (rpm_check(release:"ALA", reference:"ghostscript-debuginfo-8.70-23.25.amzn1")) flag++;
if (rpm_check(release:"ALA", reference:"ghostscript-devel-8.70-23.25.amzn1")) flag++;
if (rpm_check(release:"ALA", reference:"ghostscript-doc-8.70-23.25.amzn1")) flag++;

if (flag)
{
  if (report_verbosity > 0) security_warning(port:0, extra:rpm_report_get());
  else security_warning(0);
  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");
}