Microsoft .NET Framework Multiple Vulnerabilities (KB4556401)

# Copyright (C) 2020 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("1.3.6.1.4.1.25623.1.0.817100");
  script_version("2021-08-11T08:56:08+0000");
  script_cve_id("CVE-2020-1108", "CVE-2020-0605");
  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:"2021-08-11 08:56:08 +0000 (Wed, 11 Aug 2021)");
  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:"2020-01-21 21:22:00 +0000 (Tue, 21 Jan 2020)");
  script_tag(name:"creation_date", value:"2020-05-13 09:18:00 +0530 (Wed, 13 May 2020)");
  script_name("Microsoft .NET Framework Multiple Vulnerabilities (KB4556401)");

  script_tag(name:"summary", value:"This host is missing a critical security
  update according to Microsoft KB4556401");

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

  script_tag(name:"insight", value:"Multiple flaws exist due to:

  - Microsoft .NET Framework fails to check the source markup of a file.

  - Microsoft .NET Framework improperly handles web requests.");

  script_tag(name:"impact", value:"Successful exploitation will allow an attacker
  to conduct a denial-of-service condition and run arbitrary code in the context
  of the current user. If the current user is logged on with administrative user
  rights, an attacker could take control of the affected system.");

  script_tag(name:"affected", value:"Microsoft .NET Framework 3.5, 4.5.2, 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2, 4.8 for Microsoft Windows 8.1 and Microsoft Windows Server 2012 R2.");

  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/4556401");
  script_category(ACT_GATHER_INFO);
  script_copyright("Copyright (C) 2020 Greenbone Networks GmbH");
  script_family("Windows : Microsoft Bulletins");
  script_dependencies("smb_reg_service_pack.nasl");
  script_require_ports(139, 445);
  script_mandatory_keys("SMB/WindowsVersion");
  exit(0);
}


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


if(hotfix_check_sp(win8_1:1, win8_1x64:1, win2012R2:1) <= 0){
  exit(0);
}

if(!registry_key_exists(key:"SOFTWARE\Microsoft\.NETFramework")){
  if(!registry_key_exists(key:"SOFTWARE\Microsoft\ASP.NET")){
    if(!registry_key_exists(key:"SOFTWARE\Microsoft\NET Framework Setup\NDP\v4\Full\")){
      exit(0);
    }
  }
}

key_list = make_list("SOFTWARE\Microsoft\.NETFramework\", "SOFTWARE\Microsoft\ASP.NET\", "SOFTWARE\Microsoft\NET Framework Setup\NDP\v4\Full\");
foreach key(key_list)
{
  if(".NETFramework" >< key)
  {
    foreach item (registry_enum_keys(key:key))
    {
      NetPath = registry_get_sz(key:key + item, item:"InstallRoot");
      if(NetPath && "\Microsoft.NET\Framework" >< NetPath)
      {
        foreach item (registry_enum_keys(key:key))
        {
          dotPath = NetPath + item;
          dllVer = fetch_file_version(sysPath:dotPath, file_name:"System.identitymodel.dll");
          if(dllVer)
          {
            ## https://support.microsoft.com/en-us/help/4552982/kb4552982
            if(version_in_range(version:dllVer, test_version:"3.0", test_version2:"3.0.4506.8840"))
            {
              vulnerable_range = "3.0 - 3.0.4506.8840";
              break;
            }
            ## https://support.microsoft.com/en-us/help/4552946/kb4552946
            else if(version_in_range(version:dllVer, test_version:"4.0.30319.30000", test_version2:"4.0.30319.36626"))
            {
              vulnerable_range = "4.0.30319.30000 - 4.0.30319.36626";
              break;
            }
            # https://support.microsoft.com/en-us/help/4552923/kb4552923
            else if(version_in_range(version:dllVer, test_version:"4.6", test_version2:"4.7.3619"))
            {
              vulnerable_range = "4.6 - 4.7.3619";
              break;
            }
            ## https://support.microsoft.com/en-us/help/4552933/kb4552933
            else if(version_in_range(version:dllVer, test_version:"4.8", test_version2:"4.8.4179"))
            {
              vulnerable_range = "4.8 - 4.8.4179";
              break;
            }
          }
        }
        if(vulnerable_range){
          break;
        }
      }
    }
  }

  if((!vulnerable_range) && "ASP.NET" >< key)
  {
    foreach item (registry_enum_keys(key:key))
    {
      dotPath = registry_get_sz(key:key + item, item:"Path");
      if(dotPath && "\Microsoft.NET\Framework" >< dotPath)
      {
        dllVer = fetch_file_version(sysPath:dotPath, file_name:"System.identitymodel.dll");
        if(dllVer)
        {
          ## https://support.microsoft.com/en-us/help/4552982/kb4552982
          if(version_in_range(version:dllVer, test_version:"3.0", test_version2:"3.0.4506.8840"))
          {
            vulnerable_range = "3.0 - 3.0.4506.8840";
            break;
          }
          ## https://support.microsoft.com/en-us/help/4552946/kb4552946
          else if(version_in_range(version:dllVer, test_version:"4.0.30319.30000", test_version2:"4.0.30319.36626"))
          {
            vulnerable_range = "4.0.30319.30000 - 4.0.30319.36626";
            break;
          }
          # https://support.microsoft.com/en-us/help/4552923/kb4552923
          else if(version_in_range(version:dllVer, test_version:"4.6", test_version2:"4.7.3619"))
          {
            vulnerable_range = "4.6 - 4.7.3619";
            break;
          }
          ## https://support.microsoft.com/en-us/help/4552933/kb4552933
          else if(version_in_range(version:dllVer, test_version:"4.8", test_version2:"4.8.4179"))
          {
            vulnerable_range = "4.8 - 4.8.4179";
            break;
          }
        }
      }
    }
  }

  ## For versions greater than 4.5 (https://docs.microsoft.com/en-us/dotnet/framework/migration-guide/how-to-determine-which-versions-are-installed#net_b)
  if((!vulnerable_range) && "NET Framework Setup" >< key)
  {
    dotPath = registry_get_sz(key:key, item:"InstallPath");
    if(dotPath && "\Microsoft.NET\Framework" >< dotPath)
    {
      dllVer = fetch_file_version(sysPath:dotPath, file_name:"System.identitymodel.dll");
      if(dllVer)
      {
        ## https://support.microsoft.com/en-us/help/4552982/kb4552982
        if(version_in_range(version:dllVer, test_version:"3.0", test_version2:"3.0.4506.8840"))
        {
          vulnerable_range = "3.0 - 3.0.4506.8840";
          break;
        }
        ## https://support.microsoft.com/en-us/help/4552946/kb4552946
        else if(version_in_range(version:dllVer, test_version:"4.0.30319.30000", test_version2:"4.0.30319.36626"))
        {
          vulnerable_range = "4.0.30319.30000 - 4.0.30319.36626";
          break;
        }
        # https://support.microsoft.com/en-us/help/4552923/kb4552923
        else if(version_in_range(version:dllVer, test_version:"4.6", test_version2:"4.7.3619"))
        {
          vulnerable_range = "4.6 - 4.7.3619";
          break;
        }
        ## https://support.microsoft.com/en-us/help/4552933/kb4552933
        else if(version_in_range(version:dllVer, test_version:"4.8", test_version2:"4.8.4179"))
        {
          vulnerable_range = "4.8 - 4.8.4179";
          break;
        }
      }
    }
  }

  if(vulnerable_range)
  {
    report = report_fixed_ver(file_checked:dotPath + "System.identitymodel.dll",
                              file_version:dllVer, vulnerable_range:vulnerable_range);
    security_message(data:report);
    exit(0);
  }
}
exit(99);