Microsoft Malware Protection Engine < 1.1.14700.5 RCE

#
# (C) Tenable Network Security, Inc.
#

include('compat.inc');

if (description)
{
  script_id(108813);
  script_version("1.12");
  script_set_attribute(attribute:"plugin_modification_date", value:"2021/06/11");

  script_cve_id("CVE-2018-0986");
  script_bugtraq_id(103593);
  script_xref(name:"IAVA", value:"2018-A-0096-S");

  script_name(english:"Microsoft Malware Protection Engine < 1.1.14700.5 RCE");

  script_set_attribute(attribute:"synopsis", value:
"An antimalware application installed on the remote host is affected by
a remote code execution vulnerability.");
  script_set_attribute(attribute:"description", value:
"The version of Microsoft Malware Protection Engine (MMPE) installed
on the remote Windows host is prior to 1.1.14700.5. It is, therefore,
affected by a remote code execution vulnerability which could allow
an attacker who successfully exploited this vulnerability to
execute arbitrary code in the security context of the LocalSystem
account and take control of the system. An attacker could then
install programs; view, change, or delete data; or create new
accounts with full user rights.

Note that Nessus has checked if a vulnerable version of MMPE is being
used by any of the following applications :

  - Microsoft Forefront Endpoint Protection 2010

  - Microsoft Forefront Endpoint Protection

  - Microsoft Exchange Server 2013 and 2016

  - Microsoft Endpoint Protection

  - Microsoft Security Essentials

  - Windows Defender for Windows 7, Windows 8.1, 
    Windows 10, Windows 10 1511, Windows 10 1607,
    Windows 10 1703, Windows 10 1709, and Windows Server 2016(SC)

  - Windows Intune Endpoint Protection");
  # https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2018-0986
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?cb49367b");
  script_set_attribute(attribute:"solution", value:
"Enable automatic updates to update the scan engine for the relevant
antimalware applications. Refer to Knowledge Base Article 2510781 for
information on how to verify that MMPE has been updated.");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:M/Au:N/C:C/I:C/A:C");
  script_set_cvss_temporal_vector("CVSS2#E:H/RL:OF/RC:C");
  script_set_cvss3_base_vector("CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H");
  script_set_cvss3_temporal_vector("CVSS:3.0/E:H/RL:O/RC:C");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2018-0986");

  script_set_attribute(attribute:"exploitability_ease", value:"Exploits are available");
  script_set_attribute(attribute:"exploit_available", value:"true");
  script_set_attribute(attribute:"exploited_by_malware", value:"true");

  script_set_attribute(attribute:"vuln_publication_date", value:"2018/04/03");
  script_set_attribute(attribute:"patch_publication_date", value:"2018/04/04");
  script_set_attribute(attribute:"plugin_publication_date", value:"2018/04/04");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:microsoft:windows");
  script_set_attribute(attribute:"cpe", value:"cpe:/a:microsoft:malware_protection_engine");
  script_set_attribute(attribute:"stig_severity", value:"I");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_family(english:"Windows");

  script_copyright(english:"This script is Copyright (C) 2018-2021 and is owned by Tenable, Inc. or an Affiliate thereof.");

  script_dependencies("smb_hotfixes.nasl", "fcs_installed.nasl");
  script_require_keys("SMB/Registry/Enumerated");
  script_require_ports(139, 445);

  exit(0);
}

include("audit.inc");
include("global_settings.inc");
include("misc_func.inc");
include("smb_func.inc");

get_kb_item_or_exit("SMB/Registry/Enumerated");

# indicates if any antimalware products were found. this is used
# to determine whether or not the plugin should check if defender is affected
antimalware_installed = FALSE;

# Connect to the appropriate share.
port    =  kb_smb_transport();
login   =  kb_smb_login();
pass    =  kb_smb_password();
domain  =  kb_smb_domain();

if(! smb_session_init()) audit(AUDIT_FN_FAIL, 'smb_session_init');

rc = NetUseAdd(login:login, password:pass, domain:domain, share:"IPC$");
if (rc != 1)
{
  NetUseDel();
  audit(AUDIT_SHARE_FAIL, "IPC$");
}

# Connect to remote registry.
hklm = RegConnectRegistry(hkey:HKEY_LOCAL_MACHINE);
if (isnull(hklm))
{
  NetUseDel();
  audit(AUDIT_REG_FAIL);
}

# Figure out where it is installed.
path = NULL;
info = '';
info2 = '';
engine_version = NULL;

fixed_engine_version = "1.1.14700.5";
last_vulnerable = "1.1.14600.4";

# Forefront Client Security (either both or neither of these will be in the KB)
engine_version = get_kb_item("Antivirus/Forefront_Client_Security/engine_version");
fcs_path = get_kb_item("Antivirus/Forefront_Client_Security/path");
if (!isnull(engine_version))
{
  antimalware_installed = TRUE;

  if (ver_compare(ver:engine_version, fix:last_vulnerable) <= 0)
  {
    info +=
      '\n  Product           : Microsoft Forefront Client Security'+
      '\n  Path              : ' + fcs_path +
      '\n  Installed version : ' + engine_version +
      '\n  Fixed version     : ' + fixed_engine_version + '\n';
  }
  else info2 += 'Microsoft Forefront Client Security with MMPE version '+ engine_version + ". ";
}

# Microsoft Security Essentials
# Forefront Endpoint Protection
# System Center Endpoint Protection
engine_version = NULL;

NetUseDel(close:FALSE);
rc = NetUseAdd(login:login, password:pass, domain:domain, share:"IPC$");
if (rc != 1)
{
  NetUseDel();
  audit(AUDIT_SHARE_FAIL, "IPC$");
}

# Connect to remote registry again.
hklm = RegConnectRegistry(hkey:HKEY_LOCAL_MACHINE);
if (isnull(hklm))
{
  NetUseDel();
  audit(AUDIT_REG_FAIL);
}

key = "SOFTWARE\Microsoft\Microsoft Antimalware\Signature Updates";
key_h = RegOpenKey(handle:hklm, key:key, mode:MAXIMUM_ALLOWED);
if (!isnull(key_h))
{
  value = RegQueryValue(handle:key_h, item:"EngineVersion");
  if (!isnull(value)) engine_version = value[1];

  RegCloseKey(handle:key_h);
}

path = NULL;
key = "SOFTWARE\Microsoft\Microsoft Antimalware";
key_h = RegOpenKey(handle:hklm, key:key, mode:MAXIMUM_ALLOWED);
if (!isnull(key_h))
{
  value = RegQueryValue(handle:key_h, item:"InstallLocation");
  if (!isnull(value)) path = value[1];

  RegCloseKey(handle:key_h);
}

if(!isnull(path))
{
  found = 0;
  # Check if the main exe exists.
  share = ereg_replace(pattern:"^([A-Za-z]):.*", replace:"\1$", string:path);
  exe =  ereg_replace(pattern:"^[A-Za-z]:(.*)", replace:"\1\MsMpEng.exe", string:path);
  NetUseDel(close:FALSE);
  rc = NetUseAdd(login:login, password:pass, domain:domain, share:share);
  if (rc != 1)
  {
    NetUseDel();
    audit(AUDIT_SHARE_FAIL, share);
  }
  fh = CreateFile(
    file:exe,
    desired_access:GENERIC_READ,
    file_attributes:FILE_ATTRIBUTE_NORMAL,
    share_mode:FILE_SHARE_READ,
    create_disposition:OPEN_EXISTING
  );
  if (!isnull(fh))
  {
    antimalware_installed = TRUE;
    found = 1;
    CloseFile(handle:fh);
  }

  if (found && !isnull(engine_version))
  {
    if (ver_compare(ver:engine_version, fix:last_vulnerable) <= 0)
    {
      info +=
       '\n  Product           : Microsoft Security Essentials / Forefront Endpoint Protection / System Center Endpoint Protection'+
       '\n  Path              : ' + share[0] + ':' + exe +
       '\n  Installed version : ' + engine_version +
       '\n  Fixed version     : ' + fixed_engine_version + '\n';
    }
    else info2 += 'Microsoft Security Essentials / Forefront Endpoint Protection / System Center Endpoint Protection with MMPE version ' + engine_version + ". ";
  }
}

# Microsoft Windows Defender
# defender is apparently disabled when other antimalware products are installed,
# so it will only be checked if the plugin hasn't detected other products are present
if (!antimalware_installed)
{
  defender_enabled = TRUE;
  engine_version = NULL;

  # Check if Windows Defender is disabled via group policy
  key = "SOFTWARE\Policies\Microsoft\Windows Defender";
  key_h = RegOpenKey(handle:hklm, key:key, mode:MAXIMUM_ALLOWED);
  if (!isnull(key_h))
  {
    value = RegQueryValue(handle:key_h, item:"DisableAntiSpyware");
    if (!isnull(value))
    {
      if (value[1] > 0)
      {
        defender_enabled = FALSE;
      }
    }
    RegCloseKey(handle:key_h);
  }
  key = "SOFTWARE\Microsoft\Windows Defender";
  key_h = RegOpenKey(handle:hklm, key:key, mode:MAXIMUM_ALLOWED);
  if (!isnull(key_h))
  {
    value = RegQueryValue(handle:key_h, item:"DisableAntiSpyware");
    if (!isnull(value))
    {
      if (value[1] > 0)
      {
        defender_enabled = FALSE;
      }
    }
    RegCloseKey(handle:key_h);
  }
  if (defender_enabled)
  {
    key = "SOFTWARE\Microsoft\Windows Defender\Signature Updates";
    key_h = RegOpenKey(handle:hklm, key:key, mode:MAXIMUM_ALLOWED);
    if (!isnull(key_h))
    {
      value = RegQueryValue(handle:key_h, item:"EngineVersion");
      if (!isnull(value)) engine_version = value[1];

      RegCloseKey(handle:key_h);
    }

    path = NULL;
    key = "SOFTWARE\Microsoft\Windows Defender\Signature Updates";
    key_h = RegOpenKey(handle:hklm, key:key, mode:MAXIMUM_ALLOWED);
    if (!isnull(key_h))
    {
      value = RegQueryValue(handle:key_h, item:"SignatureLocation");
      if (!isnull(value)) path = value[1];

      RegCloseKey(handle:key_h);
    }

    if(!isnull(path))
    {
      found = 0;
      defender_dll = NULL;
      # Check the version of the main exe.
      share = ereg_replace(pattern:"^([A-Za-z]):.*", replace:"\1$", string:path);
      # this is the path smb_kb4022344.nasl checks
      dll1 =  ereg_replace(pattern:"^[A-Za-z]:(.+Windows Defender\\Definition Updates).+", replace:"\1\Default\MpEngine.dll", string:path);
      # this path works for Windows Defender on Windows 8
      dll2 =  ereg_replace(pattern:"^[A-Za-z]:(.+)$", replace:"\1\MpEngine.dll", string:path);
      NetUseDel(close:FALSE);
      rc = NetUseAdd(login:login, password:pass, domain:domain, share:share);
      if (rc != 1)
      {
        NetUseDel();
        audit(AUDIT_SHARE_FAIL, share);
      }
      fh = CreateFile(
        file:dll1,
        desired_access:GENERIC_READ,
        file_attributes:FILE_ATTRIBUTE_NORMAL,
        share_mode:FILE_SHARE_READ,
        create_disposition:OPEN_EXISTING
      );
      if (!isnull(fh))
      {
        found =1 ;
        defender_dll = share[0] + ':' + dll1;
        CloseFile(handle:fh);
      }

      if (found == 0)
      {
        fh = CreateFile(
          file:dll2,
          desired_access:GENERIC_READ,
          file_attributes:FILE_ATTRIBUTE_NORMAL,
          share_mode:FILE_SHARE_READ,
          create_disposition:OPEN_EXISTING
        );
        if (!isnull(fh))
        {
          found =1 ;
          defender_dll = share[0] + ':' + dll2;
          CloseFile(handle:fh);
        }
      }

      if (found && !isnull(engine_version))
      {
        if (ver_compare(ver:engine_version, fix:last_vulnerable) <= 0)
        {
          info +=
           '\n  Product           : Microsoft Windows Defender'+
           '\n  Path              : ' + defender_dll +
           '\n  Installed version : ' + engine_version +
           '\n  Fixed version     : ' + fixed_engine_version + '\n';
        }
        else info2 += 'Microsoft Windows Defender with MMPE version ' + engine_version + ". ";
      }
    }
  }
}

RegCloseKey(handle:hklm);
NetUseDel();

if (info)
{
  report = '\n' +
    "Nessus found following vulnerable product(s) installed :" +'\n'+
    info;
  security_report_v4(severity:SECURITY_HOLE, port:port, extra:report);

  exit(0);
}
else if(info2) exit(0,"The following instance(s) of MMPE are installed and not vulnerable : "+ info2);
else exit(0, "Nessus could not find evidence of affected Microsoft antimalware products installed.");