Security Updates for Exchange (July 2021) - Nessus

High Plugin ID: 151664

This page contains detailed information about the Security Updates for Exchange (July 2021) Nessus plugin including available exploits and PoCs found on GitHub, in Metasploit or Exploit-DB for verifying of this vulnerability.

Table Of Contents

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Plugin Overview
Vulnerability Information

Synopsis
Description
Solution

Public Exploits
Risk Information
Plugin Source
How to Run
References
Version

Plugin Overview

ID: 151664
Name: Security Updates for Exchange (July 2021)
Filename: smb_nt_ms21_jul_exchange.nasl
Vulnerability Published: 2021-07-13
This Plugin Published: 2021-07-15
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: 2021-07-13
Patch Published: 2021-07-13
CVE [?]: CVE-2021-31196, CVE-2021-31206, CVE-2021-33768, CVE-2021-34470
CPE [?]: cpe:/a:microsoft:exchange_server
Exploited by Malware: True

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 can exploit this to bypass authentication and execute unauthorized arbitrary commands. (CVE-2021-31196, CVE-2021-31206)

- An elevation of privilege vulnerability. An attacker can exploit this to gain elevated privileges. (CVE-2021-33768, CVE-2021-34470)

Note: Nessus is unable to determine if the latest Active Directory schema has been applied.

Solution

Microsoft has released the following KBs to address these issues: - KB5003611 - KB5003612 - KB5004778 - KB5004779 - KB5004780

Public Exploits

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

Here's the list of publicly known exploits and PoCs for verifying the Security Updates for Exchange (July 2021) vulnerability:

GitHub: https://github.com/Astrogeorgeonethree/Starred
[CVE-2021-31196]
GitHub: https://github.com/FDlucifer/Proxy-Attackchain
[CVE-2021-31196]
GitHub: https://github.com/hosch3n/ProxyVulns
[CVE-2021-31196]
GitHub: https://github.com/technion/CVE-2021-34470scanner
[CVE-2021-34470: A Powrshell script to scan for CVE-2021-34470]

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-2021-31206
CVSS V2 Vector: AV:A/AC:M/Au:N/C:C/I:C/A:C/E:H/RL:OF/RC:C

CVSS Base Score:	7.9 (High)
Impact Subscore:	10.0
Exploitability Subscore:	5.5
CVSS Temporal Score:	6.9 (Medium)
CVSS Environmental Score:	NA (None)
Modified Impact Subscore:	NA
Overall CVSS Score:	6.9 (Medium)

CVSS V3 Vector: CVSS:3.0/AV:A/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H/E:H/RL:O/RC:C

CVSS Base Score:	8.0 (High)
Impact Subscore:	5.9
Exploitability Subscore:	2.1
CVSS Temporal Score:	7.6 (High)
CVSS Environmental Score:	NA (None)
Modified Impact Subscore:	NA
Overall CVSS Score:	7.6 (High)

STIG Severity [?]: I
STIG Risk Rating: High

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Plugin Source

#%NASL_MIN_LEVEL 70300
##
# (C) Tenable Network Security, Inc.
##

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

if (description)
{
  script_id(151664);
  script_version("1.8");
  script_set_attribute(attribute:"plugin_modification_date", value:"2022/04/04");

  script_cve_id(
    "CVE-2021-31196",
    "CVE-2021-31206",
    "CVE-2021-33768",
    "CVE-2021-34470"
  );
  script_xref(name:"MSKB", value:"5003611");
  script_xref(name:"MSFT", value:"MS21-5003611");
  script_xref(name:"MSKB", value:"5003612");
  script_xref(name:"MSFT", value:"MS21-5003612");
  script_xref(name:"MSKB", value:"5004778");
  script_xref(name:"MSFT", value:"MS21-5004778");
  script_xref(name:"MSKB", value:"5004779");
  script_xref(name:"MSFT", value:"MS21-5004779");
  script_xref(name:"MSKB", value:"5004780");
  script_xref(name:"MSFT", value:"MS21-5004780");
  script_xref(name:"IAVA", value:"2021-A-0315-S");

  script_name(english:"Security Updates for Exchange (July 2021)");

  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 can exploit this to bypass
  authentication and execute unauthorized arbitrary commands.  (CVE-2021-31196,
  CVE-2021-31206)

- An elevation of privilege vulnerability. An attacker can exploit this to gain
  elevated privileges. (CVE-2021-33768, CVE-2021-34470)

Note: Nessus is unable to determine if the latest Active Directory schema has
been applied.");
  # https://support.microsoft.com/en-us/topic/description-of-the-security-update-for-microsoft-exchange-server-2016-july-13-2021-kb5004779-81e40da3-60db-4c09-bf11-b8c1e0c1b77d
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?a44a0d8a");
  # https://support.microsoft.com/en-us/topic/description-of-the-security-update-for-microsoft-exchange-server-2019-july-13-2021-kb5004780-fc5b3fa1-1f7a-47b0-8014-699257256bb5
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?4f529b54");
  # https://support.microsoft.com/en-us/topic/description-of-the-security-update-for-microsoft-exchange-server-2013-july-13-2021-kb5004778-f532100d-a9c1-4f2c-bc36-baec95881011
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?ecec1115");
  # https://support.microsoft.com/en-us/topic/cumulative-update-21-for-exchange-server-2016-kb5003611-b7ba1656-abba-4a0b-9be9-dac45095d969
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?51a55048");
  # https://support.microsoft.com/en-us/topic/cumulative-update-10-for-exchange-server-2019-kb5003612-b1434cad-3fbc-4dc3-844d-82568e8d4344
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?c76ecd10");
  script_set_attribute(attribute:"solution", value:
"Microsoft has released the following KBs to address these issues:
 - KB5003611
 - KB5003612
 - KB5004778
 - KB5004779
 - KB5004780");
  script_set_cvss_base_vector("CVSS2#AV:A/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:A/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-2021-31206");

  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:"2021/07/13");
  script_set_attribute(attribute:"patch_publication_date", value:"2021/07/13");
  script_set_attribute(attribute:"plugin_publication_date", value:"2021/07/15");

  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) 2021-2022 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': '15.0.1497.23'
  },
  {
    'product': '2016',
    'unsupported_cu': 19,
    'cu' : 20,
    'min_version': '15.01.2242.0',
    'fixed_version': '15.01.2242.12'
  },
  {
     'product' : '2016',
     'unsupported_cu' : 19,
     'cu' : 21,
     'min_version': '15.01.2308.0',
     'fixed_version': '15.01.2308.14'
   },
  {
     'product' : '2019',
     'unsupported_cu' : 8,
     'cu' : 9,
     'min_version': '15.02.858.0',
     'fixed_version': '15.02.858.15'
   },
  {
    'product' : '2019',
    'unsupported_cu' : 8,
    'cu' : 10,
    'min_version': '15.02.922.0',
    'fixed_version': '15.02.922.13'
  }

];

vcf::microsoft::exchange::check_version_and_report
(
  app_info:app_info,
  bulletin:'MS21-07',
  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_ms21_jul_exchange.nasl
Windows:
C:\ProgramData\Tenable\Nessus\nessus\plugins\smb_nt_ms21_jul_exchange.nasl
Mac OS X:
/Library/Nessus/run/lib/nessus/plugins/smb_nt_ms21_jul_exchange.nasl

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How to Run

Here is how to run the Security Updates for Exchange (July 2021) as a standalone plugin via the Nessus web user interface (https://localhost:8834/):

Click to start a New Scan.
Select Advanced Scan.
Navigate to the Plugins tab.
On the top right corner click to Disable All plugins.
On the left side table select Windows : Microsoft Bulletins plugin family.
On the right side table select Security Updates for Exchange (July 2021) plugin ID 151664.
Specify the target on the Settings tab and click to Save the scan.
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_ms21_jul_exchange.nasl -t <IP/HOST>

Run the plugin with audit trail message on the console:

/opt/nessus/bin/nasl -a smb_nt_ms21_jul_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_ms21_jul_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_ms21_jul_exchange.nasl -t <IP/HOST>

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References

MSKB | Microsoft Knowledge Base:

5003611, 5003612, 5004778, 5004779, 5004780

MSFT | Microsoft Security Bulletin:

MS21-5003611, MS21-5003612, MS21-5004778, MS21-5004779, MS21-5004780

IAVA | Information Assurance Vulnerability Alert:

2021-A-0315-S

See also:

Similar and related Nessus plugins:

153822 - FreeBSD : Node.js -- July 2021 Security Releases (c174118e-1b11-11ec-9d9d-0022489ad614)
152123 - NVIDIA Linux GPU Display Driver (July 2021)
152124 - NVIDIA Windows GPU Display Driver (July 2021)
152033 - Oracle JDeveloper XXE (July 2021 CPU)
152035 - Oracle WebLogic Server Multiple Vulnerabilities (July 2021 CPU)
151606 - KB5004237: Windows 10 Version 2004 / Windows 10 Version 20H2 / Windows 10 Version 21H1 Security Update (July 2021)
151592 - KB5004238: Windows 10 Version 1607 / Windows Server 2016 Security Update (July 2021)
151588 - KB5004244: Windows 10 version 1809 / Windows Server 2019 Security Update (July 2021)
151604 - KB5004245: Windows 10 1909 Security Update (July 2021)
151596 - KB5004249: Windows 10 1507 LTS Security Update (July 2021)
151599 - KB5004302: Windows Server 2012 Security Update (July 2021)
151598 - KB5004298: Windows Server 2012 R2 Security Update (July 2021)
151601 - KB5004305: Windows Server 2008 Security Update (July 2021)
151611 - KB5004307: Windows 7 and Windows Server 2008 R2 Security Update (July 2021)
151471 - KB5004945: Windows 10 2004 / 20H2 / 21H1 OOB Security Update RCE (July 2021)
151472 - KB5004946: Windows 10 1909 OOB Security Update RCE (July 2021)
151473 - KB5004947: Windows 10 1809 and Windows Server 2019 OOB Security Update RCE (July 2021)
151474 - KB5004948: Windows 10 1607 and Windows Server 2016 OOB Security Update RCE (July 2021)
151475 - KB5004950: Windows 10 1507 LTS OOB Security Update RCE (July 2021)
151476 - KB5004951: Windows Server 2008 R2 OOB Security Update RCE (July 2021)
151477 - KB5004958: Windows Server 2012 R2 OOB Security Update RCE (July 2021)
151478 - KB5004959: Windows Server 2008 OOB Security Update RCE (July 2021)
151479 - KB5004960: Windows Server 2012 OOB Security Update RCE (July 2021)
151488 - Windows PrintNightmare Registry Exposure CVE-2021-34527 OOB Security Update RCE (July 2021)

Version

This page has been produced using Nessus Professional 10.1.2 (#68) LINUX, Plugin set 202205072148.
Plugin file smb_nt_ms21_jul_exchange.nasl version 1.8. For more plugins, visit the Nessus Plugin Library.

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Security Updates for Exchange (July 2021) - Nessus

Plugin Overview

Vulnerability Information

Synopsis

Description

Solution

Public Exploits

Risk Information

Plugin Source

How to Run

References

Version

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