Microsoft Office Word Viewer Security Feature Bypass Vulnerability (KB4462154)

# Copyright (C) 2019 Greenbone Networks GmbH
# Some text descriptions might be excerpted from (a) referenced
# source(s), and are Copyright (C) by the respective right holder(s).
#
# SPDX-License-Identifier: GPL-2.0-or-later
#
# This program is free software; you can redistribute it and/or
# modify it under the terms of the GNU General Public License
# as published by the Free Software Foundation; either version 2
# of the License, or (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

if(description)
{
  script_oid("1.3.6.1.4.1.25623.1.0.814742");
  script_version("2020-06-04T09:02:37+0000");
  script_cve_id("CVE-2019-0540");
  script_bugtraq_id(106863);
  script_tag(name:"cvss_base", value:"4.3");
  script_tag(name:"cvss_base_vector", value:"AV:N/AC:M/Au:N/C:N/I:P/A:N");
  script_tag(name:"last_modification", value:"2020-06-04 09:02:37 +0000 (Thu, 04 Jun 2020)");
  script_tag(name:"creation_date", value:"2019-02-13 10:55:46 +0530 (Wed, 13 Feb 2019)");
  script_name("Microsoft Office Word Viewer Security Feature Bypass Vulnerability (KB4462154)");

  script_tag(name:"summary", value:"This host is missing an important security
  update according to Microsoft KB4462154");

  script_tag(name:"vuldetect", value:"Checks if a vulnerable version is present on the target host.");

  script_tag(name:"insight", value:"The flaw exists due to an error when Microsoft
  Office does not validate URLs.");

  script_tag(name:"impact", value:"Successful exploitation will allow an attacker
  to send a victim a specially crafted file, which could trick the victim into
  entering credentials.");

  script_tag(name:"affected", value:"Microsoft Office Word Viewer.");

  script_tag(name:"solution", value:"The vendor has released updates. Please see the references for more information.");

  script_tag(name:"solution_type", value:"VendorFix");
  script_tag(name:"qod_type", value:"executable_version");
  script_xref(name:"URL", value:"https://support.microsoft.com/en-us/help/4462154");
  script_category(ACT_GATHER_INFO);
  script_copyright("Copyright (C) 2019 Greenbone Networks GmbH");
  script_family("Windows : Microsoft Bulletins");
  script_dependencies("secpod_office_products_version_900032.nasl");
  script_mandatory_keys("SMB/Office/WordView/Version");
  script_require_ports(139, 445);
  exit(0);
}


include("smb_nt.inc");
include("host_details.inc");
include("version_func.inc");
include("secpod_smb_func.inc");

if(!os_arch = get_kb_item("SMB/Windows/Arch")){
  exit(0);
}

if("x86" >< os_arch){
  key_list = make_list("SOFTWARE\Microsoft\Windows\CurrentVersion");
}
else if("x64" >< os_arch){
  key_list =  make_list("SOFTWARE\Wow6432Node\Microsoft\Windows\CurrentVersion",
                        "SOFTWARE\Microsoft\Windows\CurrentVersion");
}

foreach key(key_list)
{
  propath = registry_get_sz(key:key, item:"CommonFilesDir");
  if(propath)
  {
    offPath = propath + "\Microsoft Shared\OFFICE11";
    exeVer = fetch_file_version(sysPath:offPath, file_name:"Mso.dll");
    if(exeVer && exeVer =~ "^(11\.)")
    {
      if(version_is_less(version:exeVer, test_version:"11.0.8453.0"))
      {
        report = report_fixed_ver(file_checked:offPath + "\Mso.dll",
                                  file_version:exeVer, vulnerable_range:"11.0 - 11.0.8452");
        security_message(data:report);
        exit(0);
      }
    }
  }
}
exit(99);