Ubuntu 14.04 LTS / 16.04 LTS / 18.04 LTS : PolicyKit vulnerability (USN-3934-1)

#
# (C) Tenable Network Security, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Ubuntu Security Notice USN-3934-1. The text 
# itself is copyright (C) Canonical, Inc. See 
# <http://www.ubuntu.com/usn/>. Ubuntu(R) is a registered 
# trademark of Canonical, Inc.
#

include('compat.inc');

if (description)
{
  script_id(123750);
  script_version("1.9");
  script_set_attribute(attribute:"plugin_modification_date", value:"2025/03/12");

  script_cve_id("CVE-2019-6133");
  script_xref(name:"USN", value:"3934-1");

  script_name(english:"Ubuntu 14.04 LTS / 16.04 LTS / 18.04 LTS : PolicyKit vulnerability (USN-3934-1)");

  script_set_attribute(attribute:"synopsis", value:
"The remote Ubuntu host is missing a security update.");
  script_set_attribute(attribute:"description", value:
"The remote Ubuntu 14.04 LTS / 16.04 LTS / 18.04 LTS host has packages installed that are affected by a vulnerability as
referenced in the USN-3934-1 advisory.

    It was discovered that PolicyKit incorrectly relied on the fork() system call in the Linux kernel being
    atomic. A local attacker could possibly use this issue to gain access to services that have cached
    authorizations.

Tenable has extracted the preceding description block directly from the Ubuntu security advisory.

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://ubuntu.com/security/notices/USN-3934-1");
  script_set_attribute(attribute:"solution", value:
"Update the affected packages.");
  script_set_cvss_base_vector("CVSS2#AV:L/AC:M/Au:N/C:P/I:P/A:P");
  script_set_cvss_temporal_vector("CVSS2#E:U/RL:OF/RC:C");
  script_set_cvss3_base_vector("CVSS:3.0/AV:L/AC:H/PR:L/UI:R/S:U/C:H/I:H/A:H");
  script_set_cvss3_temporal_vector("CVSS:3.0/E:U/RL:O/RC:C");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2019-6133");
  script_set_attribute(attribute:"cvss3_score_rationale", value:"Scoring adjustsed to align with CVSS 3.1 attack complexity guidance.");

  script_set_attribute(attribute:"exploitability_ease", value:"No known exploits are available");
  script_set_attribute(attribute:"exploit_available", value:"false");

  script_set_attribute(attribute:"vuln_publication_date", value:"2019/01/11");
  script_set_attribute(attribute:"patch_publication_date", value:"2019/04/03");
  script_set_attribute(attribute:"plugin_publication_date", value:"2019/04/04");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:libpolkit-backend-1-0");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:libpolkit-backend-1-dev");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:libpolkit-gobject-1-0");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:libpolkit-gobject-1-dev");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:policykit-1");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:14.04:-:lts");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:16.04:-:lts");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:18.04:-:lts");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:gir1.2-polkit-1.0");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:libpolkit-agent-1-0");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:libpolkit-agent-1-dev");
  script_set_attribute(attribute:"generated_plugin", value:"current");
  script_end_attributes();

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

  script_copyright(english:"Ubuntu Security Notice (C) 2019-2025 Canonical, Inc. / NASL script (C) 2019-2025 and is owned by Tenable, Inc. or an Affiliate thereof.");

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

  exit(0);
}

include('debian_package.inc');

if ( ! get_kb_item('Host/local_checks_enabled') ) audit(AUDIT_LOCAL_CHECKS_NOT_ENABLED);
var os_release = get_kb_item('Host/Ubuntu/release');
if ( isnull(os_release) ) audit(AUDIT_OS_NOT, 'Ubuntu');
os_release = chomp(os_release);
if (! ('14.04' >< os_release || '16.04' >< os_release || '18.04' >< os_release)) audit(AUDIT_OS_NOT, 'Ubuntu 14.04 / 16.04 / 18.04', 'Ubuntu ' + os_release);
if ( ! get_kb_item('Host/Debian/dpkg-l') ) audit(AUDIT_PACKAGE_LIST_MISSING);

var cpu = get_kb_item('Host/cpu');
if (isnull(cpu)) audit(AUDIT_UNKNOWN_ARCH);
if ('x86_64' >!< cpu && cpu !~ "^i[3-6]86$" && 's390' >!< cpu && 'aarch64' >!< cpu) audit(AUDIT_LOCAL_CHECKS_NOT_IMPLEMENTED, 'Ubuntu', cpu);

var pkgs = [
    {'osver': '14.04', 'pkgname': 'gir1.2-polkit-1.0', 'pkgver': '0.105-4ubuntu3.14.04.6'},
    {'osver': '14.04', 'pkgname': 'libpolkit-agent-1-0', 'pkgver': '0.105-4ubuntu3.14.04.6'},
    {'osver': '14.04', 'pkgname': 'libpolkit-agent-1-dev', 'pkgver': '0.105-4ubuntu3.14.04.6'},
    {'osver': '14.04', 'pkgname': 'libpolkit-backend-1-0', 'pkgver': '0.105-4ubuntu3.14.04.6'},
    {'osver': '14.04', 'pkgname': 'libpolkit-backend-1-dev', 'pkgver': '0.105-4ubuntu3.14.04.6'},
    {'osver': '14.04', 'pkgname': 'libpolkit-gobject-1-0', 'pkgver': '0.105-4ubuntu3.14.04.6'},
    {'osver': '14.04', 'pkgname': 'libpolkit-gobject-1-dev', 'pkgver': '0.105-4ubuntu3.14.04.6'},
    {'osver': '14.04', 'pkgname': 'policykit-1', 'pkgver': '0.105-4ubuntu3.14.04.6'},
    {'osver': '16.04', 'pkgname': 'gir1.2-polkit-1.0', 'pkgver': '0.105-14.1ubuntu0.5'},
    {'osver': '16.04', 'pkgname': 'libpolkit-agent-1-0', 'pkgver': '0.105-14.1ubuntu0.5'},
    {'osver': '16.04', 'pkgname': 'libpolkit-agent-1-dev', 'pkgver': '0.105-14.1ubuntu0.5'},
    {'osver': '16.04', 'pkgname': 'libpolkit-backend-1-0', 'pkgver': '0.105-14.1ubuntu0.5'},
    {'osver': '16.04', 'pkgname': 'libpolkit-backend-1-dev', 'pkgver': '0.105-14.1ubuntu0.5'},
    {'osver': '16.04', 'pkgname': 'libpolkit-gobject-1-0', 'pkgver': '0.105-14.1ubuntu0.5'},
    {'osver': '16.04', 'pkgname': 'libpolkit-gobject-1-dev', 'pkgver': '0.105-14.1ubuntu0.5'},
    {'osver': '16.04', 'pkgname': 'policykit-1', 'pkgver': '0.105-14.1ubuntu0.5'},
    {'osver': '18.04', 'pkgname': 'gir1.2-polkit-1.0', 'pkgver': '0.105-20ubuntu0.18.04.5'},
    {'osver': '18.04', 'pkgname': 'libpolkit-agent-1-0', 'pkgver': '0.105-20ubuntu0.18.04.5'},
    {'osver': '18.04', 'pkgname': 'libpolkit-agent-1-dev', 'pkgver': '0.105-20ubuntu0.18.04.5'},
    {'osver': '18.04', 'pkgname': 'libpolkit-backend-1-0', 'pkgver': '0.105-20ubuntu0.18.04.5'},
    {'osver': '18.04', 'pkgname': 'libpolkit-backend-1-dev', 'pkgver': '0.105-20ubuntu0.18.04.5'},
    {'osver': '18.04', 'pkgname': 'libpolkit-gobject-1-0', 'pkgver': '0.105-20ubuntu0.18.04.5'},
    {'osver': '18.04', 'pkgname': 'libpolkit-gobject-1-dev', 'pkgver': '0.105-20ubuntu0.18.04.5'},
    {'osver': '18.04', 'pkgname': 'policykit-1', 'pkgver': '0.105-20ubuntu0.18.04.5'}
];

var flag = 0;
foreach var package_array ( pkgs ) {
  var osver = NULL;
  var pkgname = NULL;
  var pkgver = NULL;
  if (!empty_or_null(package_array['osver'])) osver = package_array['osver'];
  if (!empty_or_null(package_array['pkgname'])) pkgname = package_array['pkgname'];
  if (!empty_or_null(package_array['pkgver'])) pkgver = package_array['pkgver'];
  if (osver && pkgname && pkgver) {
    if (ubuntu_check(osver:osver, pkgname:pkgname, pkgver:pkgver)) flag++;
  }
}

if (flag)
{
  var extra = '';
  extra += ubuntu_report_get();
  security_report_v4(
    port       : 0,
    severity   : SECURITY_WARNING,
    extra      : extra
  );
  exit(0);
}
else
{
  var tested = ubuntu_pkg_tests_get();
  if (tested) audit(AUDIT_PACKAGE_NOT_AFFECTED, tested);
  else audit(AUDIT_PACKAGE_NOT_INSTALLED, 'gir1.2-polkit-1.0 / libpolkit-agent-1-0 / libpolkit-agent-1-dev / etc');
}