Debian DSA-4972-1 : ghostscript - security update

#%NASL_MIN_LEVEL 70300
#
# (C) Tenable Network Security, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Debian Security Advisory dsa-4972. The text
# itself is copyright (C) Software in the Public Interest, Inc.
#

include('deprecated_nasl_level.inc');
include('compat.inc');

if (description)
{
  script_id(153215);
  script_version("1.7");
  script_set_attribute(attribute:"plugin_modification_date", value:"2024/04/09");

  script_cve_id("CVE-2021-3781");
  script_xref(name:"IAVB", value:"2021-B-0055-S");

  script_name(english:"Debian DSA-4972-1 : ghostscript - security update");

  script_set_attribute(attribute:"synopsis", value:
"The remote Debian host is missing a security-related update.");
  script_set_attribute(attribute:"description", value:
"The remote Debian 11 host has packages installed that are affected by a vulnerability as referenced in the dsa-4972
advisory.

  - A trivial sandbox (enabled with the `-dSAFER` option) escape flaw was found in the ghostscript interpreter
    by injecting a specially crafted pipe command. This flaw allows a specially crafted document to execute
    arbitrary commands on the system in the context of the ghostscript interpreter. The highest threat from
    this vulnerability is to confidentiality, integrity, as well as system availability. (CVE-2021-3781)

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version
number.");
  script_set_attribute(attribute:"see_also", value:"https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=994011");
  script_set_attribute(attribute:"see_also", value:"https://security-tracker.debian.org/tracker/source-package/ghostscript");
  script_set_attribute(attribute:"see_also", value:"https://www.debian.org/security/2021/dsa-4972");
  script_set_attribute(attribute:"see_also", value:"https://security-tracker.debian.org/tracker/CVE-2021-3781");
  script_set_attribute(attribute:"see_also", value:"https://packages.debian.org/source/bullseye/ghostscript");
  script_set_attribute(attribute:"solution", value:
"Upgrade the ghostscript packages.

For the stable distribution (bullseye), this problem has been fixed in version 9.53.3~dfsg-7+deb11u1.");
  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:POC/RL:OF/RC:C");
  script_set_cvss3_base_vector("CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:C/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-2021-3781");

  script_set_attribute(attribute:"exploitability_ease", value:"Exploits are available");
  script_set_attribute(attribute:"exploit_available", value:"true");

  script_set_attribute(attribute:"vuln_publication_date", value:"2021/09/10");
  script_set_attribute(attribute:"patch_publication_date", value:"2021/09/10");
  script_set_attribute(attribute:"plugin_publication_date", value:"2021/09/10");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:ghostscript");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:ghostscript-doc");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:ghostscript-x");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:libgs-dev");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:libgs9");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:libgs9-common");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:debian:debian_linux:11.0");
  script_set_attribute(attribute:"stig_severity", value:"I");
  script_end_attributes();

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

  script_copyright(english:"This script is Copyright (C) 2021-2024 and is owned by Tenable, Inc. or an Affiliate thereof.");

  script_dependencies("ssh_get_info.nasl");
  script_require_keys("Host/local_checks_enabled", "Host/Debian/release", "Host/Debian/dpkg-l");

  exit(0);
}

include('audit.inc');
include('debian_package.inc');

if (!get_kb_item("Host/local_checks_enabled")) audit(AUDIT_LOCAL_CHECKS_NOT_ENABLED);
if (!get_kb_item("Host/Debian/dpkg-l")) audit(AUDIT_PACKAGE_LIST_MISSING);

var release = get_kb_item('Host/Debian/release');
if ( isnull(release) ) audit(AUDIT_OS_NOT, 'Debian');
var release = chomp(release);
if (! preg(pattern:"^(11)\.[0-9]+", string:release)) audit(AUDIT_OS_NOT, 'Debian 11.0', 'Debian ' + release);
var cpu = get_kb_item('Host/cpu');
if (isnull(cpu)) audit(AUDIT_UNKNOWN_ARCH);
if ('x86_64' >!< cpu && cpu !~ "^i[3-6]86$" && 'aarch64' >!< cpu) audit(AUDIT_LOCAL_CHECKS_NOT_IMPLEMENTED, 'Debian', cpu);

var pkgs = [
    {'release': '11.0', 'prefix': 'ghostscript', 'reference': '9.53.3~dfsg-7+deb11u1'},
    {'release': '11.0', 'prefix': 'ghostscript-doc', 'reference': '9.53.3~dfsg-7+deb11u1'},
    {'release': '11.0', 'prefix': 'ghostscript-x', 'reference': '9.53.3~dfsg-7+deb11u1'},
    {'release': '11.0', 'prefix': 'libgs-dev', 'reference': '9.53.3~dfsg-7+deb11u1'},
    {'release': '11.0', 'prefix': 'libgs9', 'reference': '9.53.3~dfsg-7+deb11u1'},
    {'release': '11.0', 'prefix': 'libgs9-common', 'reference': '9.53.3~dfsg-7+deb11u1'}
];

var flag = 0;
foreach package_array ( pkgs ) {
  var release = NULL;
  var prefix = NULL;
  var reference = NULL;
  if (!empty_or_null(package_array['release'])) release = package_array['release'];
  if (!empty_or_null(package_array['prefix'])) prefix = package_array['prefix'];
  if (!empty_or_null(package_array['reference'])) reference = package_array['reference'];
  if (release && prefix && reference) {
    if (deb_check(release:release, prefix:prefix, reference:reference)) flag++;
  }
}

if (flag)
{
  security_report_v4(
    port       : 0,
    severity   : SECURITY_HOLE,
    extra      : deb_report_get()
  );
  exit(0);
}
else
{
  var tested = deb_pkg_tests_get();
  if (tested) audit(AUDIT_PACKAGE_NOT_AFFECTED, tested);
  else audit(AUDIT_PACKAGE_NOT_INSTALLED, 'ghostscript / ghostscript-doc / ghostscript-x / libgs-dev / libgs9 / etc');
}