Security Updates for Microsoft Exchange Server (December 2020) - Nessus

High   Plugin ID: 143557

This page contains detailed information about the Security Updates for Microsoft Exchange Server (December 2020) Nessus plugin including available exploits and PoCs found on GitHub, in Metasploit or Exploit-DB for verifying of this vulnerability.

Plugin Overview


ID: 143557
Name: Security Updates for Microsoft Exchange Server (December 2020)
Filename: smb_nt_ms20_dec_exchange.nasl
Vulnerability Published: 2020-12-08
This Plugin Published: 2020-12-08
Last Modification Time: 2022-04-04
Plugin Version: 1.8
Plugin Type: local
Plugin Family: Windows : Microsoft Bulletins
Dependencies: microsoft_exchange_installed.nbin, ms_bulletin_checks_possible.nasl
Required KB Items [?]: SMB/MS_Bulletin_Checks/Possible

Vulnerability Information


Severity: High
Vulnerability Published: 2020-12-08
Patch Published: 2020-12-08
CVE [?]: CVE-2020-17117, CVE-2020-17132, CVE-2020-17141, CVE-2020-17142, CVE-2020-17143
CPE [?]: cpe:/a:microsoft:exchange_server

Synopsis

The Microsoft Exchange Server installed on the remote host is affected by multiple vulnerabilities.

Description

The Microsoft Exchange Server installed on the remote host is missing security updates. It is, therefore, affected by multiple vulnerabilities:

- A remote code execution vulnerability. An attacker could exploit this to execute unauthorized arbitrary code. (CVE-2020-17117, CVE-2020-17132, CVE-2020-17141, CVE-2020-17142)

- An information disclosure vulnerability. An attacker can exploit this to disclose potentially sensitive information. (CVE-2020-17143)

Solution

Microsoft has released the following security updates to address this issue: -KB4593465 -KB4593466

Public Exploits


Target Network Port(s): 139, 445
Target Asset(s): Host/patch_management_checks
Exploit Available: True (Metasploit Framework, GitHub)
Exploit Ease: Exploits are available

Here's the list of publicly known exploits and PoCs for verifying the Security Updates for Microsoft Exchange Server (December 2020) vulnerability:

  1. Metasploit: exploit/windows/http/exchange_ecp_dlp_policy
    [Microsoft Exchange Server DlpUtils AddTenantDlpPolicy RCE]
  2. GitHub: https://github.com/SexyBeast233/SecBooks
    [CVE-2020-17141]
  3. GitHub: https://github.com/EdgeSecurityTeam/Vulnerability
    [CVE-2020-17143]

Before running any exploit against any system, make sure you are authorized by the owner of the target system(s) to perform such activity. In any other case, this would be considered as an illegal activity.

WARNING: Beware of using unverified exploits from sources such as GitHub or Exploit-DB. These exploits and PoCs could contain malware. For more information, see how to use exploits safely.

Risk Information


CVSS Score Source [?]: CVE-2020-17117
CVSS V2 Vector: AV:N/AC:L/Au:S/C:C/I:C/A:C/E:F/RL:OF/RC:C
CVSS Base Score:9.0 (High)
Impact Subscore:10.0
Exploitability Subscore:8.0
CVSS Temporal Score:7.4 (High)
CVSS Environmental Score:NA (None)
Modified Impact Subscore:NA
Overall CVSS Score:7.4 (High)
CVSS V3 Vector: CVSS:3.0/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H/E:F/RL:O/RC:C
CVSS Base Score:7.2 (High)
Impact Subscore:5.9
Exploitability Subscore:1.2
CVSS Temporal Score:6.7 (Medium)
CVSS Environmental Score:NA (None)
Modified Impact Subscore:NA
Overall CVSS Score:6.7 (Medium)
STIG Severity [?]: I
STIG Risk Rating: High

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Plugin Source


This is the smb_nt_ms20_dec_exchange.nasl nessus plugin source code. This script is Copyright (C) 2020-2022 and is owned by Tenable, Inc. or an Affiliate thereof.

#%NASL_MIN_LEVEL 70300
#
# (C) Tenable Network Security, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from the Microsoft Security Updates API. The text
# itself is copyright (C) Microsoft Corporation.
#

include('deprecated_nasl_level.inc');
include('compat.inc');

if (description)
{
  script_id(143557);
  script_version("1.8");
  script_set_attribute(attribute:"plugin_modification_date", value:"2022/04/04");

  script_cve_id(
    "CVE-2020-17117",
    "CVE-2020-17132",
    "CVE-2020-17141",
    "CVE-2020-17142",
    "CVE-2020-17143"
  );
  script_xref(name:"MSKB", value:"4593465");
  script_xref(name:"MSFT", value:"MS20-4593465");
  script_xref(name:"MSKB", value:"4593466");
  script_xref(name:"MSFT", value:"MS20-4593466");
  script_xref(name:"IAVA", value:"2020-A-0554-S");

  script_name(english:"Security Updates for Microsoft Exchange Server (December 2020)");

  script_set_attribute(attribute:"synopsis", value:
"The Microsoft Exchange Server installed on the remote host is affected by
multiple vulnerabilities.");
  script_set_attribute(attribute:"description", value:
"The Microsoft Exchange Server installed on the remote host
is missing security updates. It is, therefore, affected by
multiple vulnerabilities:

  - A remote code execution vulnerability. An attacker could exploit this to
  execute unauthorized arbitrary code. (CVE-2020-17117, CVE-2020-17132,
  CVE-2020-17141, CVE-2020-17142)

  - An information disclosure vulnerability. An attacker can exploit this to
  disclose potentially sensitive information. (CVE-2020-17143)");
  # https://support.microsoft.com/en-us/help/4593465/description-of-the-security-update-for-microsoft-exchange-server-2019
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?923093df");
  # https://support.microsoft.com/en-us/help/4593466/description-of-the-security-update-for-microsoft-exchange-server-2013
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?6a67cb27");
  script_set_attribute(attribute:"solution", value:
"Microsoft has released the following security updates to address this issue:
  -KB4593465
  -KB4593466");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:S/C:C/I:C/A:C");
  script_set_cvss_temporal_vector("CVSS2#E:F/RL:OF/RC:C");
  script_set_cvss3_base_vector("CVSS:3.0/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H");
  script_set_cvss3_temporal_vector("CVSS:3.0/E:F/RL:O/RC:C");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2020-17117");

  script_set_attribute(attribute:"exploitability_ease", value:"Exploits are available");
  script_set_attribute(attribute:"exploit_available", value:"true");
  script_set_attribute(attribute:"metasploit_name", value:'Microsoft Exchange Server DlpUtils AddTenantDlpPolicy RCE');
  script_set_attribute(attribute:"exploit_framework_metasploit", value:"true");

  script_set_attribute(attribute:"vuln_publication_date", value:"2020/12/08");
  script_set_attribute(attribute:"patch_publication_date", value:"2020/12/08");
  script_set_attribute(attribute:"plugin_publication_date", value:"2020/12/08");

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

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

  script_copyright(english:"This script is Copyright (C) 2020-2022 and is owned by Tenable, Inc. or an Affiliate thereof.");

  script_dependencies("ms_bulletin_checks_possible.nasl", "microsoft_exchange_installed.nbin");
  script_require_keys("SMB/MS_Bulletin_Checks/Possible");
  script_require_ports(139, 445, "Host/patch_management_checks");

  exit(0);
}

include('vcf_extras_microsoft.inc');

var app_info = vcf::microsoft::exchange::get_app_info();

var constraints =
[
  {
    'product' : '2013',
    'unsupported_cu' : 22,
    'cu' : 23,
    'min_version': '15.00.1497.0',
    'fixed_version': '15.00.1497.10',
    'kb': '4593466'
  },
  {
    'product': '2016',
    'unsupported_cu': 16,
    'cu' : 17,
    'min_version': '15.01.2044.0',
    'fixed_version': '15.01.2044.12',
    'kb': '4593465'
  },
  {
    'product' : '2016',
    'unsupported_cu' : 16,
    'cu' : 18,
    'min_version': '15.01.2106.0',
    'fixed_version': '15.01.2106.6',
    'kb': '4593465'
  },
 {
    'product' : '2019',
    'unsupported_cu' : 5,
    'cu' : 6,
    'min_version': '15.02.659.0',
    'fixed_version': '15.02.659.11',
    'kb': '4593465'
  },
  {
    'product' : '2019',
    'unsupported_cu' : 5,
    'cu' : 7,
    'min_version': '15.02.721.0',
    'fixed_version': '15.02.721.6',
    'kb': '4593465'
  }
];

vcf::microsoft::exchange::check_version_and_report
(
  app_info:app_info,
  bulletin:'MS20-12',
  constraints:constraints,
  severity:SECURITY_WARNING
);

The latest version of this script can be found in these locations depending on your platform:

  • Linux / Unix:
    /opt/nessus/lib/nessus/plugins/smb_nt_ms20_dec_exchange.nasl
  • Windows:
    C:\ProgramData\Tenable\Nessus\nessus\plugins\smb_nt_ms20_dec_exchange.nasl
  • Mac OS X:
    /Library/Nessus/run/lib/nessus/plugins/smb_nt_ms20_dec_exchange.nasl

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How to Run


Here is how to run the Security Updates for Microsoft Exchange Server (December 2020) as a standalone plugin via the Nessus web user interface (https://localhost:8834/):

  1. Click to start a New Scan.
  2. Select Advanced Scan.
  3. Navigate to the Plugins tab.
  4. On the top right corner click to Disable All plugins.
  5. On the left side table select Windows : Microsoft Bulletins plugin family.
  6. On the right side table select Security Updates for Microsoft Exchange Server (December 2020) plugin ID 143557.
  7. Specify the target on the Settings tab and click to Save the scan.
  8. Run the scan.

Here are a few examples of how to run the plugin in the command line. Note that the examples below demonstrate the usage on the Linux / Unix platform.

Basic usage:

/opt/nessus/bin/nasl smb_nt_ms20_dec_exchange.nasl -t <IP/HOST>

Run the plugin with audit trail message on the console:

/opt/nessus/bin/nasl -a smb_nt_ms20_dec_exchange.nasl -t <IP/HOST>

Run the plugin with trace script execution written to the console (useful for debugging):

/opt/nessus/bin/nasl -T - smb_nt_ms20_dec_exchange.nasl -t <IP/HOST>

Run the plugin with using a state file for the target and updating it (useful for running multiple plugins on the target):

/opt/nessus/bin/nasl -K /tmp/state smb_nt_ms20_dec_exchange.nasl -t <IP/HOST>

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References


MSKB | Microsoft Knowledge Base: MSFT | Microsoft Security Bulletin:
  • MS20-4593465, MS20-4593466
IAVA | Information Assurance Vulnerability Alert:
  • 2020-A-0554-S
See also: Similar and related Nessus plugins:
  • 143561 - KB4592440: Windows 10 Version 1809 and Windows Server 2019 December 2020 Security Update
  • 143558 - KB4592438: Windows 10 Version 2004 December 2020 Security Update
  • 143571 - KB4592446: Windows 10 Version 1803 December 2020 Security Update
  • 143570 - KB4592449: Windows 10 Version 1903 and Windows 10 Version 1909 December 2020 Security Update
  • 143564 - Security Updates for Microsoft Excel Products (December 2020)
  • 143566 - Security Update for Microsoft Exchange Server 2010 SP 3 (December 2020)
  • 143556 - Security Updates for Microsoft Office Online Server and Microsoft Office Web Apps (December 2020)

Version


This page has been produced using Nessus Professional 10.1.2 (#68) LINUX, Plugin set 202205072148.
Plugin file smb_nt_ms20_dec_exchange.nasl version 1.8. For more plugins, visit the Nessus Plugin Library.

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