Microsoft SharePoint Enterprise Server 2016 Multiple RCE Vulnerabilities (KB4484277)

# SPDX-FileCopyrightText: 2020 Greenbone AG
# 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-only

CPE = "cpe:/a:microsoft:sharepoint_server";

if(description)
{
  script_oid("1.3.6.1.4.1.25623.1.0.816598");
  script_version("2025-08-05T05:45:17+0000");
  script_cve_id("CVE-2020-0850", "CVE-2020-0892", "CVE-2020-0852");
  script_tag(name:"cvss_base", value:"9.3");
  script_tag(name:"cvss_base_vector", value:"AV:N/AC:M/Au:N/C:C/I:C/A:C");
  script_tag(name:"last_modification", value:"2025-08-05 05:45:17 +0000 (Tue, 05 Aug 2025)");
  script_tag(name:"severity_vector", value:"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H");
  script_tag(name:"severity_origin", value:"NVD");
  script_tag(name:"severity_date", value:"2020-05-04 14:14:00 +0000 (Mon, 04 May 2020)");
  script_tag(name:"creation_date", value:"2020-03-11 10:10:57 +0000 (Wed, 11 Mar 2020)");
  script_name("Microsoft SharePoint Enterprise Server 2016 Multiple RCE Vulnerabilities (KB4484277)");

  script_tag(name:"summary", value:"This host is missing a critical security
  update according to Microsoft KB4484277.");

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

  script_tag(name:"insight", value:"Multiple flaws exist when Microsoft Word
  software fails to properly handle objects in memory.");

  script_tag(name:"impact", value:"Successful exploitation allows attackers to
  use a specially crafted file to perform actions in the security context of the
  current user.");

  script_tag(name:"affected", value:"Microsoft SharePoint Server 2019.");

  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/4484277");
  script_category(ACT_GATHER_INFO);
  script_copyright("Copyright (C) 2020 Greenbone AG");
  script_family("Windows : Microsoft Bulletins");
  script_dependencies("gb_microsoft_sharepoint_smb_login_detect.nasl");
  script_mandatory_keys("microsoft/sharepoint/server/smb-login/detected");
  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(isnull(port = get_app_port(cpe:CPE, service:"smb-login")))
  exit(0);

if(!infos = get_app_version_and_location(cpe:CPE, port:port, exit_no_version:TRUE))
  exit(0);

shareVer = infos["version"];
if(shareVer !~ "^16\.")
  exit(0);

path = infos["location"];
if(!path || "Could not find the install location" >< path)
{
  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)
  {
    path = registry_get_sz(key:key, item:"ProgramFilesDir");
    if(path)
    {
      path = path + "\Microsoft Office Servers\16.0\WebServices\ConversionServices\1033";
      dllVer = fetch_file_version(sysPath:path, file_name:"msoserverintl.dll");
      if(dllVer) {
        break;
      }
    }
  }
} else {
  path = path + "\16.0\WebServices\ConversionServices\1033";
  dllVer = fetch_file_version(sysPath:path, file_name:"msoserverintl.dll");
}

if(dllVer =~ "^16\.0\." && version_in_range(version:dllVer, test_version:"16.0.10337.12109", test_version2:"16.0.10357.20003"))
{
  report = report_fixed_ver(file_checked:path + "\msoserverintl.dll",
                            file_version:dllVer, vulnerable_range:"16.0.10337.12109 - 16.0.10357.20003");
  security_message(port:port, data:report);
  exit(0);
}

exit(99);