Ubuntu 16.04 LTS / 18.04 LTS : Samba vulnerabilities (USN-4244-1)

#
# (C) Tenable Network Security, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Ubuntu Security Notice USN-4244-1. 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(133178);
  script_version("1.10");
  script_set_attribute(attribute:"plugin_modification_date", value:"2024/08/27");

  script_cve_id("CVE-2019-14902", "CVE-2019-14907", "CVE-2019-19344");
  script_xref(name:"USN", value:"4244-1");

  script_name(english:"Ubuntu 16.04 LTS / 18.04 LTS : Samba vulnerabilities (USN-4244-1)");

  script_set_attribute(attribute:"synopsis", value:
"The remote Ubuntu host is missing one or more security updates.");
  script_set_attribute(attribute:"description", value:
"The remote Ubuntu 16.04 LTS / 18.04 LTS host has packages installed that are affected by multiple vulnerabilities as
referenced in the USN-4244-1 advisory.

    It was discovered that Samba did not automatically replicate ACLs set to inherit down a subtree on AD
    Directory, contrary to expectations. This issue was only addressed in Ubuntu 18.04 LTS, Ubuntu 19.04 and
    Ubuntu 19.10. (CVE-2019-14902)

    Robert wicki discovered that Samba incorrectly handled certain character conversions when the log
    level is set to 3 or above. In certain environments, a remote attacker could possibly use this issue to
    cause Samba to crash, resulting in a denial of service. (CVE-2019-14907)

    Christian Naumer discovered that Samba incorrectly handled DNS zone scavenging. This issue could possibly
    result in some incorrect data being written to the DB. This issue only applied to Ubuntu 19.04 and Ubuntu
    19.10. (CVE-2019-19344)

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

Note that Nessus has not tested for these issues 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-4244-1");
  script_set_attribute(attribute:"solution", value:
"Update the affected packages.");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:S/C:P/I:P/A:N");
  script_set_cvss_temporal_vector("CVSS2#E:U/RL:OF/RC:C");
  script_set_cvss3_base_vector("CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N");
  script_set_cvss3_temporal_vector("CVSS:3.0/E:U/RL:O/RC:C");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2019-14902");

  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:"2020/01/21");
  script_set_attribute(attribute:"patch_publication_date", value:"2020/01/21");
  script_set_attribute(attribute:"plugin_publication_date", value:"2020/01/22");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:samba");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:samba-common");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:samba-common-bin");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:samba-dev");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:samba-dsdb-modules");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:samba-libs");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:samba-testsuite");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:samba-vfs-modules");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:smbclient");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:winbind");
  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:ctdb");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:libnss-winbind");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:libpam-winbind");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:libparse-pidl-perl");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:libsmbclient");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:libsmbclient-dev");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:libwbclient-dev");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:libwbclient0");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:python-samba");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:registry-tools");
  script_set_attribute(attribute:"generated_plugin", value:"current");
  script_set_attribute(attribute:"stig_severity", value:"I");
  script_end_attributes();

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

  script_copyright(english:"Ubuntu Security Notice (C) 2020-2024 Canonical, Inc. / NASL script (C) 2020-2024 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 (! ('16.04' >< os_release || '18.04' >< os_release)) audit(AUDIT_OS_NOT, 'Ubuntu 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': '16.04', 'pkgname': 'ctdb', 'pkgver': '2:4.3.11+dfsg-0ubuntu0.16.04.25'},
    {'osver': '16.04', 'pkgname': 'libnss-winbind', 'pkgver': '2:4.3.11+dfsg-0ubuntu0.16.04.25'},
    {'osver': '16.04', 'pkgname': 'libpam-winbind', 'pkgver': '2:4.3.11+dfsg-0ubuntu0.16.04.25'},
    {'osver': '16.04', 'pkgname': 'libparse-pidl-perl', 'pkgver': '2:4.3.11+dfsg-0ubuntu0.16.04.25'},
    {'osver': '16.04', 'pkgname': 'libsmbclient', 'pkgver': '2:4.3.11+dfsg-0ubuntu0.16.04.25'},
    {'osver': '16.04', 'pkgname': 'libsmbclient-dev', 'pkgver': '2:4.3.11+dfsg-0ubuntu0.16.04.25'},
    {'osver': '16.04', 'pkgname': 'libwbclient-dev', 'pkgver': '2:4.3.11+dfsg-0ubuntu0.16.04.25'},
    {'osver': '16.04', 'pkgname': 'libwbclient0', 'pkgver': '2:4.3.11+dfsg-0ubuntu0.16.04.25'},
    {'osver': '16.04', 'pkgname': 'python-samba', 'pkgver': '2:4.3.11+dfsg-0ubuntu0.16.04.25'},
    {'osver': '16.04', 'pkgname': 'registry-tools', 'pkgver': '2:4.3.11+dfsg-0ubuntu0.16.04.25'},
    {'osver': '16.04', 'pkgname': 'samba', 'pkgver': '2:4.3.11+dfsg-0ubuntu0.16.04.25'},
    {'osver': '16.04', 'pkgname': 'samba-common', 'pkgver': '2:4.3.11+dfsg-0ubuntu0.16.04.25'},
    {'osver': '16.04', 'pkgname': 'samba-common-bin', 'pkgver': '2:4.3.11+dfsg-0ubuntu0.16.04.25'},
    {'osver': '16.04', 'pkgname': 'samba-dev', 'pkgver': '2:4.3.11+dfsg-0ubuntu0.16.04.25'},
    {'osver': '16.04', 'pkgname': 'samba-dsdb-modules', 'pkgver': '2:4.3.11+dfsg-0ubuntu0.16.04.25'},
    {'osver': '16.04', 'pkgname': 'samba-libs', 'pkgver': '2:4.3.11+dfsg-0ubuntu0.16.04.25'},
    {'osver': '16.04', 'pkgname': 'samba-testsuite', 'pkgver': '2:4.3.11+dfsg-0ubuntu0.16.04.25'},
    {'osver': '16.04', 'pkgname': 'samba-vfs-modules', 'pkgver': '2:4.3.11+dfsg-0ubuntu0.16.04.25'},
    {'osver': '16.04', 'pkgname': 'smbclient', 'pkgver': '2:4.3.11+dfsg-0ubuntu0.16.04.25'},
    {'osver': '16.04', 'pkgname': 'winbind', 'pkgver': '2:4.3.11+dfsg-0ubuntu0.16.04.25'},
    {'osver': '18.04', 'pkgname': 'ctdb', 'pkgver': '2:4.7.6+dfsg~ubuntu-0ubuntu2.15'},
    {'osver': '18.04', 'pkgname': 'libnss-winbind', 'pkgver': '2:4.7.6+dfsg~ubuntu-0ubuntu2.15'},
    {'osver': '18.04', 'pkgname': 'libpam-winbind', 'pkgver': '2:4.7.6+dfsg~ubuntu-0ubuntu2.15'},
    {'osver': '18.04', 'pkgname': 'libparse-pidl-perl', 'pkgver': '2:4.7.6+dfsg~ubuntu-0ubuntu2.15'},
    {'osver': '18.04', 'pkgname': 'libsmbclient', 'pkgver': '2:4.7.6+dfsg~ubuntu-0ubuntu2.15'},
    {'osver': '18.04', 'pkgname': 'libsmbclient-dev', 'pkgver': '2:4.7.6+dfsg~ubuntu-0ubuntu2.15'},
    {'osver': '18.04', 'pkgname': 'libwbclient-dev', 'pkgver': '2:4.7.6+dfsg~ubuntu-0ubuntu2.15'},
    {'osver': '18.04', 'pkgname': 'libwbclient0', 'pkgver': '2:4.7.6+dfsg~ubuntu-0ubuntu2.15'},
    {'osver': '18.04', 'pkgname': 'python-samba', 'pkgver': '2:4.7.6+dfsg~ubuntu-0ubuntu2.15'},
    {'osver': '18.04', 'pkgname': 'registry-tools', 'pkgver': '2:4.7.6+dfsg~ubuntu-0ubuntu2.15'},
    {'osver': '18.04', 'pkgname': 'samba', 'pkgver': '2:4.7.6+dfsg~ubuntu-0ubuntu2.15'},
    {'osver': '18.04', 'pkgname': 'samba-common', 'pkgver': '2:4.7.6+dfsg~ubuntu-0ubuntu2.15'},
    {'osver': '18.04', 'pkgname': 'samba-common-bin', 'pkgver': '2:4.7.6+dfsg~ubuntu-0ubuntu2.15'},
    {'osver': '18.04', 'pkgname': 'samba-dev', 'pkgver': '2:4.7.6+dfsg~ubuntu-0ubuntu2.15'},
    {'osver': '18.04', 'pkgname': 'samba-dsdb-modules', 'pkgver': '2:4.7.6+dfsg~ubuntu-0ubuntu2.15'},
    {'osver': '18.04', 'pkgname': 'samba-libs', 'pkgver': '2:4.7.6+dfsg~ubuntu-0ubuntu2.15'},
    {'osver': '18.04', 'pkgname': 'samba-testsuite', 'pkgver': '2:4.7.6+dfsg~ubuntu-0ubuntu2.15'},
    {'osver': '18.04', 'pkgname': 'samba-vfs-modules', 'pkgver': '2:4.7.6+dfsg~ubuntu-0ubuntu2.15'},
    {'osver': '18.04', 'pkgname': 'smbclient', 'pkgver': '2:4.7.6+dfsg~ubuntu-0ubuntu2.15'},
    {'osver': '18.04', 'pkgname': 'winbind', 'pkgver': '2:4.7.6+dfsg~ubuntu-0ubuntu2.15'}
];

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, 'ctdb / libnss-winbind / libpam-winbind / libparse-pidl-perl / etc');
}