Vulnerability-Lookup

CVE-2021-42321 (GCVE-0-2021-42321)

Vulnerability from cvelistv5 – Published: 2021-11-10 00:47 – Updated: 2026-08-19 16:27

CISA Previdian

Title

Microsoft Exchange Server Remote Code Execution Vulnerability

Summary

Microsoft Exchange Server Remote Code Execution Vulnerability

Severity

8.8 (High)


                        
                          CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C

SSVC

Exploitation: active Automatable: no Technical Impact: total

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2024-01-03 16:43 UTC

CWE

Remote Code Execution
CWE-noinfo Not enough information

Assigner

microsoft mitre root

References

5 references

URL	Tags
https://msrc.microsoft.com/update-guide/vulnerabi…	vendor-advisorypatch
https://portal.msrc.microsoft.com/en-US/security-…	x_refsource_MISCx_transferred
http://packetstormsecurity.com/files/166153/Micro…	x_refsource_MISCx_transferred
http://packetstormsecurity.com/files/168131/Micro…	x_refsource_MISCx_transferred
https://www.cisa.gov/known-exploited-vulnerabilit…	government-resource

Impacted products

4 products

Vendor	Product	Version	CPE status
Microsoft	Microsoft Exchange Server 2016 Cumulative Update 21	Affected: 15.01.0 , < 15.01.2308.020 (custom)	guessed
Microsoft	Microsoft Exchange Server 2016 Cumulative Update 22	Affected: 15.0.0 , < 15.01.2375.017 (custom)	guessed
Microsoft	Microsoft Exchange Server 2019 Cumulative Update 10	Affected: 15.02.0 , < 15.02.0792.019 (custom)	guessed
Microsoft	Microsoft Exchange Server 2019 Cumulative Update 11	Affected: 15.02.0 , < 15.02.0986.014 (custom)	guessed

Date Public

2021-11-09 08:00

CISA

Known Exploited Vulnerability - GCVE BCP-07 Compliant

KEV entry ID: 9b7db247-27ae-47ae-909b-1ad1759da672

Vulnerability ID: CVE-2021-42321

Status: Confirmed

Status Updated: 2021-11-17 00:00 UTC

Exploited: Yes

Timestamps

First Seen: 2021-11-17

Asserted: 2021-11-17

Scope

Notes: KEV entry: Microsoft Exchange Server Remote Code Execution Vulnerability | Affected: Microsoft / Exchange | Description: An authenticated attacker could leverage improper validation in cmdlet arguments within Microsoft Exchange and perform remote code execution. | Required action: Apply updates per vendor instructions. | Due date: 2021-12-01 | Known ransomware campaign use (KEV): Known | Notes (KEV): https://nvd.nist.gov/vuln/detail/CVE-2021-42321

Evidence

Type: Vendor Report

Signal: Successful Exploitation

Confidence: 80%

Source: cisa-kev

Details

Cwes	CWE-184 CWE-502
Feed	CISA Known Exploited Vulnerabilities Catalog
Product	Exchange
Due Date	2021-12-01
Date Added	2021-11-17
Vendorproject	Microsoft
Vulnerabilityname	Microsoft Exchange Server Remote Code Execution Vulnerability
Knownransomwarecampaignuse	Known

References

CVE-2021-42321

Created: 2026-02-02 13:26 UTC | Updated: 2026-02-06 07:53 UTC

Previdian

Known Exploited Vulnerability - GCVE BCP-07 Compliant

KEV entry ID: 4a15b265-e22c-4418-a04d-81d9153c2e32

Vulnerability ID: CVE-2021-42321

Status: Confirmed

Status Updated: 2021-11-17 00:00 UTC

Exploited: Yes

Timestamps

First Seen: 2021-11-17

Asserted: 2021-11-17

Scope

Notes: KEVIntel entry: Microsoft Exchange Server Remote Code Execution Vulnerability | Affected: Microsoft / Microsoft Exchange Server 2016 Cumulative Update 21, Microsoft Exchange Server 2019 Cumulative Update 10, Microsoft Exchange Server 2016 Cumulative Update 22, Microsoft Exchange Server 2019 Cumulative Update 11 | CVSS: 8.8 (HIGH) | Used in malware: yes | Not yet in CISA KEV: False

Evidence

Type: Public Report

Signal: Confirmed Compromise

Confidence: 70%

Source: kevintel

Details

Feed	KEVIntel (kevintel.com)
Title	Microsoft Exchange Server Remote Code Execution Vulnerability
Vendor	Microsoft
Product	Microsoft Exchange Server 2016 Cumulative Update 21, Microsoft Exchange Server 2019 Cumulative Update 10, Microsoft Exchange Server 2016 Cumulative Update 22, Microsoft Exchange Server 2019 Cumulative Update 11
Added Date	2021-11-17T00:00:00.000Z
Cvss Score	8.8
Epss Score	None
Cvss Severity	HIGH
Epss Percentile	None
Used In Malware	yes
Ahead Of Cisa Kev	None
Not Yet In Cisa Kev	False

References

Created: 2026-06-23 11:13 UTC | Updated: 2026-06-23 11:13 UTC

Show details on NVD website

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                "descriptions": [
                  {
                    "description": "CWE-noinfo Not enough information",
                    "lang": "en",
                    "type": "CWE"
                  }
                ]
              }
            ],
            "providerMetadata": {
              "dateUpdated": "2025-02-04T19:04:59.268Z",
              "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
              "shortName": "CISA-ADP"
            },
            "references": [
              {
                "tags": [
                  "government-resource"
                ],
                "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-42321"
              }
            ],
            "timeline": [
              {
                "lang": "en",
                "time": "2021-11-17T00:00:00.000Z",
                "value": "CVE-2021-42321 added to CISA KEV"
              }
            ],
            "title": "CISA ADP Vulnrichment"
          }
        ],
        "cna": {
          "affected": [
            {
              "platforms": [
                "x64-based Systems"
              ],
              "product": "Microsoft Exchange Server 2016 Cumulative Update 21",
              "vendor": "Microsoft",
              "versions": [
                {
                  "lessThan": "15.01.2308.020",
                  "status": "affected",
                  "version": "15.01.0",
                  "versionType": "custom"
                }
              ]
            },
            {
              "platforms": [
                "x64-based Systems"
              ],
              "product": "Microsoft Exchange Server 2016 Cumulative Update 22",
              "vendor": "Microsoft",
              "versions": [
                {
                  "lessThan": "15.01.2375.017",
                  "status": "affected",
                  "version": "15.0.0",
                  "versionType": "custom"
                }
              ]
            },
            {
              "platforms": [
                "x64-based Systems"
              ],
              "product": "Microsoft Exchange Server 2019 Cumulative Update 10",
              "vendor": "Microsoft",
              "versions": [
                {
                  "lessThan": "15.02.0792.019",
                  "status": "affected",
                  "version": "15.02.0",
                  "versionType": "custom"
                }
              ]
            },
            {
              "platforms": [
                "x64-based Systems"
              ],
              "product": "Microsoft Exchange Server 2019 Cumulative Update 11",
              "vendor": "Microsoft",
              "versions": [
                {
                  "lessThan": "15.02.0986.014",
                  "status": "affected",
                  "version": "15.02.0",
                  "versionType": "custom"
                }
              ]
            }
          ],
          "cpeApplicability": [
            {
              "nodes": [
                {
                  "cpeMatch": [
                    {
                      "criteria": "cpe:2.3:a:microsoft:exchange_server:*:cumulative_update_21:*:*:*:*:*:*",
                      "versionEndExcluding": "15.01.2308.020",
                      "versionStartIncluding": "15.01.0",
                      "vulnerable": true
                    },
                    {
                      "criteria": "cpe:2.3:a:microsoft:exchange_server:*:cumulative_update_10:*:*:*:*:*:*",
                      "versionEndExcluding": "15.02.0792.019",
                      "versionStartIncluding": "15.02.0",
                      "vulnerable": true
                    },
                    {
                      "criteria": "cpe:2.3:a:microsoft:exchange_server:*:cumulative_update_22:*:*:*:*:*:*",
                      "versionEndExcluding": "15.01.2375.017",
                      "versionStartIncluding": "15.0.0",
                      "vulnerable": true
                    },
                    {
                      "criteria": "cpe:2.3:a:microsoft:exchange_server:*:cumulative_update_11:*:*:*:*:*:*",
                      "versionEndExcluding": "15.02.0986.014",
                      "versionStartIncluding": "15.02.0",
                      "vulnerable": true
                    }
                  ],
                  "negate": false,
                  "operator": "OR"
                }
              ]
            }
          ],
          "datePublic": "2021-11-09T08:00:00.000Z",
          "descriptions": [
            {
              "lang": "en-US",
              "value": "Microsoft Exchange Server Remote Code Execution Vulnerability"
            }
          ],
          "metrics": [
            {
              "cvssV3_1": {
                "baseScore": 8.8,
                "baseSeverity": "HIGH",
                "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C",
                "version": "3.1"
              },
              "format": "CVSS",
              "scenarios": [
                {
                  "lang": "en-US",
                  "value": "GENERAL"
                }
              ]
            }
          ],
          "problemTypes": [
            {
              "descriptions": [
                {
                  "description": "Remote Code Execution",
                  "lang": "en-US",
                  "type": "Impact"
                }
              ]
            }
          ],
          "providerMetadata": {
            "dateUpdated": "2026-08-19T16:27:07.165Z",
            "orgId": "f38d906d-7342-40ea-92c1-6c4a2c6478c8",
            "shortName": "microsoft"
          },
          "references": [
            {
              "name": "Microsoft Exchange Server Remote Code Execution Vulnerability",
              "tags": [
                "vendor-advisory",
                "patch"
              ],
              "url": "https://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-42321"
            }
          ],
          "title": "Microsoft Exchange Server Remote Code Execution Vulnerability"
        }
      },
      "cveMetadata": {
        "assignerOrgId": "f38d906d-7342-40ea-92c1-6c4a2c6478c8",
        "assignerShortName": "microsoft",
        "cveId": "CVE-2021-42321",
        "datePublished": "2021-11-10T00:47:43.000Z",
        "dateReserved": "2021-10-12T00:00:00.000Z",
        "dateUpdated": "2026-08-19T16:27:07.165Z",
        "state": "PUBLISHED"
      },
      "dataType": "CVE_RECORD",
      "dataVersion": "5.2"
    }
  }
}

BDU:2021-05330 (CVE-2021-42321)

Vulnerability from fstec – Published: 2021-11-10 – Updated: 2026-08-24 – View on bdu.fstec.ru Exploit publicly available Yes Fixed

CISA Previdian

Title

Уязвимость почтового сервера Microsoft Exchange Server, связанная с недостаточной проверкой аргументов командлета, позволяющая нарушителю выполнить произвольный код

Summary

Уязвимость почтового сервера Microsoft Exchange Server связана с недостаточной проверкой аргументов командлета. Эксплуатация уязвимости может позволить нарушителю, действующему удаленно, выполнить произвольный код

Severity

9.0 (High) CVSS 2.0


                      
                        AV:N/AC:L/Au:S/C:C/I:C/A:C

9.6 (Critical) CVSS 3.0


                      
                        CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H

Class

Code vulnerability

Status

Confirmed by the vendor

Exploitation

Data structure manipulation

Incidents

Yes

Remediation

Software update

CWE

CWE-20 - Недостаточная проверка вводимых данных

Aliases

CVE-2021-42321

References

5 references

URL
https://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-42321
https://www.cybersecurity-help.cz/vdb/SB2021110928
https://techcommunity.microsoft.com/t5/exchange-team-blog/released-november-202…
https://www.zerodayinitiative.com/blog/2021/11/9/the-november-2021-security-upd…
http://packetstormsecurity.com/files/166153/Microsoft-Exchange-Server-Remote-Co…

Impacted products

1 product from 1 vendor

Vendors

Microsoft Corp

Products

Microsoft Exchange Server

Versions

2019 Cumulative Update 10 (Microsoft Exchange Server), 2016 Cumulative Update 21 (Microsoft Exchange Server), 2019 Cumulative Update 11 (Microsoft Exchange Server), 2016 Cumulative Update 22 (Microsoft Exchange Server)

Product types

Application software

Mitigations

Использование рекомендаций: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-42321

JSON

To clipboard

{
  "CVSS 2.0": "AV:N/AC:L/Au:S/C:C/I:C/A:C",
  "CVSS 3.0": "AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H",
  "CVSS 4.0": null,
  "remediation_\u0418\u0434\u0435\u043d\u0442\u0438\u0444\u0438\u043a\u0430\u0442\u043e\u0440": null,
  "remediation_\u041d\u0430\u0438\u043c\u0435\u043d\u043e\u0432\u0430\u043d\u0438\u0435": null,
  "\u0412\u0435\u043d\u0434\u043e\u0440 \u041f\u041e": "Microsoft Corp",
  "\u0412\u0435\u0440\u0441\u0438\u044f \u041f\u041e": "2019 Cumulative Update 10 (Microsoft Exchange Server), 2016 Cumulative Update 21 (Microsoft Exchange Server), 2019 Cumulative Update 11 (Microsoft Exchange Server), 2016 Cumulative Update 22 (Microsoft Exchange Server)",
  "\u0412\u043e\u0437\u043c\u043e\u0436\u043d\u044b\u0435 \u043c\u0435\u0440\u044b \u043f\u043e \u0443\u0441\u0442\u0440\u0430\u043d\u0435\u043d\u0438\u044e": "\u0418\u0441\u043f\u043e\u043b\u044c\u0437\u043e\u0432\u0430\u043d\u0438\u0435 \u0440\u0435\u043a\u043e\u043c\u0435\u043d\u0434\u0430\u0446\u0438\u0439:\nhttps://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-42321",
  "\u0414\u0430\u0442\u0430 \u0432\u044b\u044f\u0432\u043b\u0435\u043d\u0438\u044f": "09.11.2021",
  "\u0414\u0430\u0442\u0430 \u043f\u043e\u0441\u043b\u0435\u0434\u043d\u0435\u0433\u043e \u043e\u0431\u043d\u043e\u0432\u043b\u0435\u043d\u0438\u044f": "24.08.2026",
  "\u0414\u0430\u0442\u0430 \u043f\u0443\u0431\u043b\u0438\u043a\u0430\u0446\u0438\u0438": "10.11.2021",
  "\u0418\u0434\u0435\u043d\u0442\u0438\u0444\u0438\u043a\u0430\u0442\u043e\u0440": "BDU:2021-05330",
  "\u0418\u0434\u0435\u043d\u0442\u0438\u0444\u0438\u043a\u0430\u0442\u043e\u0440\u044b \u0434\u0440\u0443\u0433\u0438\u0445 \u0441\u0438\u0441\u0442\u0435\u043c \u043e\u043f\u0438\u0441\u0430\u043d\u0438\u0439 \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u0438": "CVE-2021-42321",
  "\u0418\u043d\u0444\u043e\u0440\u043c\u0430\u0446\u0438\u044f \u043e\u0431 \u0443\u0441\u0442\u0440\u0430\u043d\u0435\u043d\u0438\u0438": "\u0423\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u044c \u0443\u0441\u0442\u0440\u0430\u043d\u0435\u043d\u0430",
  "\u041a\u043b\u0430\u0441\u0441 \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u0438": "\u0423\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u044c \u043a\u043e\u0434\u0430",
  "\u041d\u0430\u0437\u0432\u0430\u043d\u0438\u0435 \u041f\u041e": "Microsoft Exchange Server",
  "\u041d\u0430\u0438\u043c\u0435\u043d\u043e\u0432\u0430\u043d\u0438\u0435 \u041e\u0421 \u0438 \u0442\u0438\u043f \u0430\u043f\u043f\u0430\u0440\u0430\u0442\u043d\u043e\u0439 \u043f\u043b\u0430\u0442\u0444\u043e\u0440\u043c\u044b": null,
  "\u041d\u0430\u0438\u043c\u0435\u043d\u043e\u0432\u0430\u043d\u0438\u0435 \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u0438": "\u0423\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u044c \u043f\u043e\u0447\u0442\u043e\u0432\u043e\u0433\u043e \u0441\u0435\u0440\u0432\u0435\u0440\u0430 Microsoft Exchange Server, \u0441\u0432\u044f\u0437\u0430\u043d\u043d\u0430\u044f \u0441 \u043d\u0435\u0434\u043e\u0441\u0442\u0430\u0442\u043e\u0447\u043d\u043e\u0439 \u043f\u0440\u043e\u0432\u0435\u0440\u043a\u043e\u0439 \u0430\u0440\u0433\u0443\u043c\u0435\u043d\u0442\u043e\u0432 \u043a\u043e\u043c\u0430\u043d\u0434\u043b\u0435\u0442\u0430, \u043f\u043e\u0437\u0432\u043e\u043b\u044f\u044e\u0449\u0430\u044f \u043d\u0430\u0440\u0443\u0448\u0438\u0442\u0435\u043b\u044e \u0432\u044b\u043f\u043e\u043b\u043d\u0438\u0442\u044c \u043f\u0440\u043e\u0438\u0437\u0432\u043e\u043b\u044c\u043d\u044b\u0439 \u043a\u043e\u0434",
  "\u041d\u0430\u043b\u0438\u0447\u0438\u0435 \u044d\u043a\u0441\u043f\u043b\u043e\u0439\u0442\u0430": "\u0421\u0443\u0449\u0435\u0441\u0442\u0432\u0443\u0435\u0442 \u0432 \u043e\u0442\u043a\u0440\u044b\u0442\u043e\u043c \u0434\u043e\u0441\u0442\u0443\u043f\u0435",
  "\u041e\u043f\u0438\u0441\u0430\u043d\u0438\u0435 \u043e\u0448\u0438\u0431\u043a\u0438 CWE": "\u041d\u0435\u0434\u043e\u0441\u0442\u0430\u0442\u043e\u0447\u043d\u0430\u044f \u043f\u0440\u043e\u0432\u0435\u0440\u043a\u0430 \u0432\u0432\u043e\u0434\u0438\u043c\u044b\u0445 \u0434\u0430\u043d\u043d\u044b\u0445 (CWE-20)",
  "\u041e\u043f\u0438\u0441\u0430\u043d\u0438\u0435 \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u0438": "\u0423\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u044c \u043f\u043e\u0447\u0442\u043e\u0432\u043e\u0433\u043e \u0441\u0435\u0440\u0432\u0435\u0440\u0430 Microsoft Exchange Server \u0441\u0432\u044f\u0437\u0430\u043d\u0430 \u0441 \u043d\u0435\u0434\u043e\u0441\u0442\u0430\u0442\u043e\u0447\u043d\u043e\u0439 \u043f\u0440\u043e\u0432\u0435\u0440\u043a\u043e\u0439 \u0430\u0440\u0433\u0443\u043c\u0435\u043d\u0442\u043e\u0432 \u043a\u043e\u043c\u0430\u043d\u0434\u043b\u0435\u0442\u0430. \u042d\u043a\u0441\u043f\u043b\u0443\u0430\u0442\u0430\u0446\u0438\u044f \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u0438 \u043c\u043e\u0436\u0435\u0442 \u043f\u043e\u0437\u0432\u043e\u043b\u0438\u0442\u044c \u043d\u0430\u0440\u0443\u0448\u0438\u0442\u0435\u043b\u044e, \u0434\u0435\u0439\u0441\u0442\u0432\u0443\u044e\u0449\u0435\u043c\u0443 \u0443\u0434\u0430\u043b\u0435\u043d\u043d\u043e, \u0432\u044b\u043f\u043e\u043b\u043d\u0438\u0442\u044c \u043f\u0440\u043e\u0438\u0437\u0432\u043e\u043b\u044c\u043d\u044b\u0439 \u043a\u043e\u0434",
  "\u041f\u043e\u0441\u043b\u0435\u0434\u0441\u0442\u0432\u0438\u044f \u044d\u043a\u0441\u043f\u043b\u0443\u0430\u0442\u0430\u0446\u0438\u0438 \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u0438": null,
  "\u041f\u0440\u043e\u0447\u0430\u044f \u0438\u043d\u0444\u043e\u0440\u043c\u0430\u0446\u0438\u044f": null,
  "\u0421\u0432\u044f\u0437\u044c \u0441 \u0438\u043d\u0446\u0438\u0434\u0435\u043d\u0442\u0430\u043c\u0438 \u0418\u0411": "\u0414\u0430",
  "\u0421\u043e\u0441\u0442\u043e\u044f\u043d\u0438\u0435 \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u0438": "\u041e\u043f\u0443\u0431\u043b\u0438\u043a\u043e\u0432\u0430\u043d\u0430",
  "\u0421\u043f\u043e\u0441\u043e\u0431 \u0443\u0441\u0442\u0440\u0430\u043d\u0435\u043d\u0438\u044f": "\u041e\u0431\u043d\u043e\u0432\u043b\u0435\u043d\u0438\u0435 \u043f\u0440\u043e\u0433\u0440\u0430\u043c\u043c\u043d\u043e\u0433\u043e \u043e\u0431\u0435\u0441\u043f\u0435\u0447\u0435\u043d\u0438\u044f",
  "\u0421\u043f\u043e\u0441\u043e\u0431 \u044d\u043a\u0441\u043f\u043b\u0443\u0430\u0442\u0430\u0446\u0438\u0438": "\u041c\u0430\u043d\u0438\u043f\u0443\u043b\u0438\u0440\u043e\u0432\u0430\u043d\u0438\u0435 \u0441\u0442\u0440\u0443\u043a\u0442\u0443\u0440\u0430\u043c\u0438 \u0434\u0430\u043d\u043d\u044b\u0445",
  "\u0421\u0441\u044b\u043b\u043a\u0438 \u043d\u0430 \u0438\u0441\u0442\u043e\u0447\u043d\u0438\u043a\u0438": "https://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-42321\nhttps://www.cybersecurity-help.cz/vdb/SB2021110928\nhttps://techcommunity.microsoft.com/t5/exchange-team-blog/released-november-2021-exchange-server-security-updates/ba-p/2933169\nhttps://www.zerodayinitiative.com/blog/2021/11/9/the-november-2021-security-update-review\nhttp://packetstormsecurity.com/files/166153/Microsoft-Exchange-Server-Remote-Code-Execution.html",
  "\u0421\u0442\u0430\u0442\u0443\u0441 \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u0438": "\u041f\u043e\u0434\u0442\u0432\u0435\u0440\u0436\u0434\u0435\u043d\u0430 \u043f\u0440\u043e\u0438\u0437\u0432\u043e\u0434\u0438\u0442\u0435\u043b\u0435\u043c",
  "\u0422\u0438\u043f \u041f\u041e": "\u041f\u0440\u0438\u043a\u043b\u0430\u0434\u043d\u043e\u0435 \u041f\u041e \u0438\u043d\u0444\u043e\u0440\u043c\u0430\u0446\u0438\u043e\u043d\u043d\u044b\u0445 \u0441\u0438\u0441\u0442\u0435\u043c",
  "\u0422\u0438\u043f \u043e\u0448\u0438\u0431\u043a\u0438 CWE": "CWE-20",
  "\u0423\u0440\u043e\u0432\u0435\u043d\u044c \u043e\u043f\u0430\u0441\u043d\u043e\u0441\u0442\u0438 \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u0438": "\u0412\u044b\u0441\u043e\u043a\u0438\u0439 \u0443\u0440\u043e\u0432\u0435\u043d\u044c \u043e\u043f\u0430\u0441\u043d\u043e\u0441\u0442\u0438 (\u0431\u0430\u0437\u043e\u0432\u0430\u044f \u043e\u0446\u0435\u043d\u043a\u0430 CVSS 2.0 \u0441\u043e\u0441\u0442\u0430\u0432\u043b\u044f\u0435\u0442 9)\n\u041a\u0440\u0438\u0442\u0438\u0447\u0435\u0441\u043a\u0438\u0439 \u0443\u0440\u043e\u0432\u0435\u043d\u044c \u043e\u043f\u0430\u0441\u043d\u043e\u0441\u0442\u0438 (\u0431\u0430\u0437\u043e\u0432\u0430\u044f \u043e\u0446\u0435\u043d\u043a\u0430 CVSS 3.0 \u0441\u043e\u0441\u0442\u0430\u0432\u043b\u044f\u0435\u0442 9,6)"
}

CERTFR-2021-ALE-021

Vulnerability from certfr_alerte - Published: 2021-11-10 - Updated: 2022-05-04

Une vulnérabilité a été découverte dans Microsoft Exchange, initialement dans le cadre de la compétition de cybersécurité Tianfu Cup qui a eu lieu en juillet 2021. Elle permet à un attaquant ayant accès aux identifiants d'un utilisateur de provoquer une exécution de code arbitraire à distance, permettant d’obtenir in fine les droits de l’administrateur de domaine Active Directory.

L'éditeur confirme que cette vulnérabilité est exploitée dans le cadre d'attaques ciblées.

Le CERT-FR recommande donc d'appliquer les correctifs de sécurité dans les plus brefs délais.

Le CERT-FR rappelle en outre que l'éditeur ne fournit des correctifs de sécurité que pour les deux dernières mises à jour cumulatives (Cumulative Update, CU). En l’occurrence, seules les versions de Microsoft Exchange 2019 CU 11, 2019 CU 10, 2016 CU 22 et 2016 CU 21 disposent d'un correctif de sécurité. Il est donc primordial d'avoir déployé ces mises à jour cumulatives (CU) et d'appliquer le correctif.

Enfin, il convient de souligner que ce type de service ne devrait pas être exposé sur Internet sans mesure de protection [1].

Solution

Se référer au bulletin de sécurité de l'éditeur pour l'obtention des correctifs (cf. section Documentation).

None

Impacted products

	Vendor	Product	Description
	Microsoft	N/A	Microsoft Exchange 2016
	Microsoft	N/A	Microsoft Exchange 2019

References

Title

Publication Time

CERTFR-2021-AVI-863

Vulnerability from certfr_avis - Published: 2021-11-10 - Updated: 2021-11-10

De multiples vulnérabilités ont été corrigées dans les produits Microsoft. Elles permettent à un attaquant de provoquer une usurpation d'identité, une atteinte à la confidentialité des données, une exécution de code à distance, une élévation de privilèges et un contournement de la fonctionnalité de sécurité.

Solution

Se référer au bulletin de sécurité de l'éditeur pour l'obtention des correctifs (cf. section Documentation).

None

Impacted products

Vendor	Product	Description
Microsoft	N/A	Microsoft Exchange Server 2013 Cumulative Update 23
Microsoft	N/A	FSLogix
Microsoft	N/A	Microsoft Visual Studio 2017 version 15.9 (includes 15.0 - 15.8)
Microsoft	N/A	Microsoft Exchange Server 2016 Cumulative Update 21
Microsoft	Azure	Azure RTOS
Microsoft	N/A	Microsoft Visual Studio 2019 version 16.7 (includes 16.0 – 16.6)
Microsoft	N/A	Microsoft Exchange Server 2019 Cumulative Update 11
Microsoft	N/A	3D Viewer
Microsoft	N/A	Microsoft Visual Studio 2019 version 16.9 (includes 16.0 - 16.8)
Microsoft	N/A	Microsoft Exchange Server 2016 Cumulative Update 22
Microsoft	N/A	Microsoft Visual Studio 2019 version 16.11 (includes 16.0 - 16.10)
Microsoft	N/A	Microsoft Malware Protection Engine
Microsoft	N/A	Power BI Report Server
Microsoft	N/A	Visual Studio Code
Microsoft	N/A	Microsoft Dynamics 365 (on-premises) version 9.1
Microsoft	N/A	Microsoft 365 Apps pour Enterprise pour systèmes 32 bits
Microsoft	N/A	Microsoft 365 Apps pour Enterprise pour 64 bits Systems
Microsoft	N/A	Microsoft Exchange Server 2019 Cumulative Update 10
Microsoft	N/A	Microsoft Visual Studio 2015 Update 3
Microsoft	Azure	Azure Sphere
Microsoft	N/A	Microsoft Dynamics 365 (on-premises) version 9.0

References

Title

Publication Time

CNVD-2021-90307

Vulnerability from cnvd - Published: 2021-11-24

Title

Microsoft Exchange Server远程代码执行漏洞（CNVD-2021-90307）

Description

Microsoft Exchange Server是美国微软（Microsoft）公司的一套电子邮件服务程序。它提供邮件存取、储存、转发，语音邮件，邮件过滤筛选等功能。 Microsoft Exchange Server存在远程代码执行漏洞，攻击者可通过发送特制的恶意数据到服务器利用该漏洞在服务器上远程执行任意代码。

Severity

中

Patch Name

Microsoft Exchange Server远程代码执行漏洞（CNVD-2021-90307）的补丁

Patch Description

Formal description

厂商已发布了漏洞修复程序，请及时关注更新： https://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-42321

Reference

https://nvd.nist.gov/vuln/detail/CVE-2021-42321

Impacted products

Name
['Microsoft Microsoft Exchange Server 2019 Cumulative Update 10', 'Microsoft Microsoft Exchange Server 2019 Cumulative Update 11', 'Microsoft Microsoft Exchange Server 2016 Cumulative Update 21', 'Microsoft Microsoft Exchange Server 2016 Cumulative Update 22']

Show details on source website

JSON

To clipboard

{
  "cves": {
    "cve": {
      "cveNumber": "CVE-2021-42321"
    }
  },
  "description": "Microsoft Exchange Server\u662f\u7f8e\u56fd\u5fae\u8f6f\uff08Microsoft\uff09\u516c\u53f8\u7684\u4e00\u5957\u7535\u5b50\u90ae\u4ef6\u670d\u52a1\u7a0b\u5e8f\u3002\u5b83\u63d0\u4f9b\u90ae\u4ef6\u5b58\u53d6\u3001\u50a8\u5b58\u3001\u8f6c\u53d1\uff0c\u8bed\u97f3\u90ae\u4ef6\uff0c\u90ae\u4ef6\u8fc7\u6ee4\u7b5b\u9009\u7b49\u529f\u80fd\u3002\n\nMicrosoft Exchange Server\u5b58\u5728\u8fdc\u7a0b\u4ee3\u7801\u6267\u884c\u6f0f\u6d1e\uff0c\u653b\u51fb\u8005\u53ef\u901a\u8fc7\u53d1\u9001\u7279\u5236\u7684\u6076\u610f\u6570\u636e\u5230\u670d\u52a1\u5668\u5229\u7528\u8be5\u6f0f\u6d1e\u5728\u670d\u52a1\u5668\u4e0a\u8fdc\u7a0b\u6267\u884c\u4efb\u610f\u4ee3\u7801\u3002",
  "formalWay": "\u5382\u5546\u5df2\u53d1\u5e03\u4e86\u6f0f\u6d1e\u4fee\u590d\u7a0b\u5e8f\uff0c\u8bf7\u53ca\u65f6\u5173\u6ce8\u66f4\u65b0\uff1a\r\nhttps://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-42321",
  "isEvent": "\u901a\u7528\u8f6f\u786c\u4ef6\u6f0f\u6d1e",
  "number": "CNVD-2021-90307",
  "openTime": "2021-11-24",
  "patchDescription": "Microsoft Exchange Server\u662f\u7f8e\u56fd\u5fae\u8f6f\uff08Microsoft\uff09\u516c\u53f8\u7684\u4e00\u5957\u7535\u5b50\u90ae\u4ef6\u670d\u52a1\u7a0b\u5e8f\u3002\u5b83\u63d0\u4f9b\u90ae\u4ef6\u5b58\u53d6\u3001\u50a8\u5b58\u3001\u8f6c\u53d1\uff0c\u8bed\u97f3\u90ae\u4ef6\uff0c\u90ae\u4ef6\u8fc7\u6ee4\u7b5b\u9009\u7b49\u529f\u80fd\u3002\r\n\r\nMicrosoft Exchange Server\u5b58\u5728\u8fdc\u7a0b\u4ee3\u7801\u6267\u884c\u6f0f\u6d1e\uff0c\u653b\u51fb\u8005\u53ef\u901a\u8fc7\u53d1\u9001\u7279\u5236\u7684\u6076\u610f\u6570\u636e\u5230\u670d\u52a1\u5668\u5229\u7528\u8be5\u6f0f\u6d1e\u5728\u670d\u52a1\u5668\u4e0a\u8fdc\u7a0b\u6267\u884c\u4efb\u610f\u4ee3\u7801\u3002\u76ee\u524d\uff0c\u4f9b\u5e94\u5546\u53d1\u5e03\u4e86\u5b89\u5168\u516c\u544a\u53ca\u76f8\u5173\u8865\u4e01\u4fe1\u606f\uff0c\u4fee\u590d\u4e86\u6b64\u6f0f\u6d1e\u3002",
  "patchName": "Microsoft Exchange Server\u8fdc\u7a0b\u4ee3\u7801\u6267\u884c\u6f0f\u6d1e\uff08CNVD-2021-90307\uff09\u7684\u8865\u4e01",
  "products": {
    "product": [
      "Microsoft Microsoft Exchange Server 2019 Cumulative Update 10",
      "Microsoft Microsoft Exchange Server 2019 Cumulative Update 11",
      "Microsoft Microsoft Exchange Server 2016 Cumulative Update 21",
      "Microsoft Microsoft Exchange Server 2016 Cumulative Update 22"
    ]
  },
  "referenceLink": "https://nvd.nist.gov/vuln/detail/CVE-2021-42321",
  "serverity": "\u4e2d",
  "submitTime": "2021-11-12",
  "title": "Microsoft Exchange Server\u8fdc\u7a0b\u4ee3\u7801\u6267\u884c\u6f0f\u6d1e\uff08CNVD-2021-90307\uff09"
}

FKIE_CVE-2021-42321

Vulnerability from fkie_nvd - Published: 2021-11-10 01:19 - Updated: 2026-08-19 19:23

CISA Previdian

Severity

8.8 (High) - CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
8.8 (High) - CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Summary

Microsoft Exchange Server Remote Code Execution Vulnerability

References

URL	Tags
secure@microsoft.com	https://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-42321	Patch, Vendor Advisory
af854a3a-2127-422b-91ae-364da2661108	http://packetstormsecurity.com/files/166153/Microsoft-Exchange-Server-Remote-Code-Execution.html	Exploit, Third Party Advisory, VDB Entry
af854a3a-2127-422b-91ae-364da2661108	http://packetstormsecurity.com/files/168131/Microsoft-Exchange-Server-ChainedSerializationBinder-Remote-Code-Execution.html	Exploit, Third Party Advisory, VDB Entry
af854a3a-2127-422b-91ae-364da2661108	https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-42321	Patch, Vendor Advisory
134c704f-9b21-4f2e-91b3-4a467353bcc0	https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-42321	US Government Resource

Impacted products

Vendor	Product	Version
microsoft	exchange_server	2016
microsoft	exchange_server	2016
microsoft	exchange_server	2019
microsoft	exchange_server	2019

JSON

To clipboard

{
  "affected": [
    {
      "affectedData": [
        {
          "platforms": [
            "x64-based Systems"
          ],
          "product": "Microsoft Exchange Server 2016 Cumulative Update 21",
          "vendor": "Microsoft",
          "versions": [
            {
              "lessThan": "15.01.2308.020",
              "status": "affected",
              "version": "15.01.0",
              "versionType": "custom"
            }
          ]
        },
        {
          "platforms": [
            "x64-based Systems"
          ],
          "product": "Microsoft Exchange Server 2016 Cumulative Update 22",
          "vendor": "Microsoft",
          "versions": [
            {
              "lessThan": "15.01.2375.017",
              "status": "affected",
              "version": "15.0.0",
              "versionType": "custom"
            }
          ]
        },
        {
          "platforms": [
            "x64-based Systems"
          ],
          "product": "Microsoft Exchange Server 2019 Cumulative Update 10",
          "vendor": "Microsoft",
          "versions": [
            {
              "lessThan": "15.02.0792.019",
              "status": "affected",
              "version": "15.02.0",
              "versionType": "custom"
            }
          ]
        },
        {
          "platforms": [
            "x64-based Systems"
          ],
          "product": "Microsoft Exchange Server 2019 Cumulative Update 11",
          "vendor": "Microsoft",
          "versions": [
            {
              "lessThan": "15.02.0986.014",
              "status": "affected",
              "version": "15.02.0",
              "versionType": "custom"
            }
          ]
        }
      ],
      "source": "secure@microsoft.com"
    }
  ],
  "cisaActionDue": "2021-12-01",
  "cisaExploitAdd": "2021-11-17",
  "cisaRequiredAction": "Apply updates per vendor instructions.",
  "cisaVulnerabilityName": "Microsoft Exchange Server Remote Code Execution Vulnerability",
  "configurations": [
    {
      "nodes": [
        {
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:a:microsoft:exchange_server:2016:cumulative_update_21:*:*:*:*:*:*",
              "matchCriteriaId": "3BE427A4-B0C2-4064-8234-29426325C348",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:a:microsoft:exchange_server:2016:cumulative_update_22:*:*:*:*:*:*",
              "matchCriteriaId": "449CE85B-E599-44D3-A7C1-5133F6A55E86",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:a:microsoft:exchange_server:2019:cumulative_update_10:*:*:*:*:*:*",
              "matchCriteriaId": "B4185347-EEDD-4239-9AB3-410E2EC89D2A",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:a:microsoft:exchange_server:2019:cumulative_update_11:*:*:*:*:*:*",
              "matchCriteriaId": "435343A4-BF10-461A-ABF2-D511A5FBDA75",
              "vulnerable": true
            }
          ],
          "negate": false,
          "operator": "OR"
        }
      ]
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "Microsoft Exchange Server Remote Code Execution Vulnerability"
    },
    {
      "lang": "es",
      "value": "Una vulnerabilidad de Ejecuci\u00f3n de C\u00f3digo Remota en Microsoft Exchange Server"
    }
  ],
  "id": "CVE-2021-42321",
  "lastModified": "2026-08-19T19:23:07.277",
  "metrics": {
    "cvssMetricV2": [
      {
        "acInsufInfo": false,
        "baseSeverity": "MEDIUM",
        "cvssData": {
          "accessComplexity": "LOW",
          "accessVector": "NETWORK",
          "authentication": "SINGLE",
          "availabilityImpact": "PARTIAL",
          "baseScore": 6.5,
          "confidentialityImpact": "PARTIAL",
          "integrityImpact": "PARTIAL",
          "vectorString": "AV:N/AC:L/Au:S/C:P/I:P/A:P",
          "version": "2.0"
        },
        "exploitabilityScore": 8.0,
        "impactScore": 6.4,
        "obtainAllPrivilege": false,
        "obtainOtherPrivilege": false,
        "obtainUserPrivilege": false,
        "source": "nvd@nist.gov",
        "type": "Primary",
        "userInteractionRequired": false
      }
    ],
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "HIGH",
          "baseScore": 8.8,
          "baseSeverity": "HIGH",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "privilegesRequired": "LOW",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
          "version": "3.1"
        },
        "exploitabilityScore": 2.8,
        "impactScore": 5.9,
        "source": "secure@microsoft.com",
        "type": "Secondary"
      },
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "HIGH",
          "baseScore": 8.8,
          "baseSeverity": "HIGH",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "privilegesRequired": "LOW",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
          "version": "3.1"
        },
        "exploitabilityScore": 2.8,
        "impactScore": 5.9,
        "source": "nvd@nist.gov",
        "type": "Secondary"
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2021-42321",
          "options": [
            {
              "exploitation": "active"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "total"
            }
          ],
          "role": "CISA Coordinator",
          "timestamp": "2024-01-03T16:43:32.753195Z",
          "version": "2.0.3"
        }
      }
    ]
  },
  "published": "2021-11-10T01:19:50.047",
  "references": [
    {
      "source": "secure@microsoft.com",
      "tags": [
        "Patch",
        "Vendor Advisory"
      ],
      "url": "https://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-42321"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "tags": [
        "Exploit",
        "Third Party Advisory",
        "VDB Entry"
      ],
      "url": "http://packetstormsecurity.com/files/166153/Microsoft-Exchange-Server-Remote-Code-Execution.html"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "tags": [
        "Exploit",
        "Third Party Advisory",
        "VDB Entry"
      ],
      "url": "http://packetstormsecurity.com/files/168131/Microsoft-Exchange-Server-ChainedSerializationBinder-Remote-Code-Execution.html"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "tags": [
        "Patch",
        "Vendor Advisory"
      ],
      "url": "https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-42321"
    },
    {
      "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
      "tags": [
        "US Government Resource"
      ],
      "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-42321"
    }
  ],
  "sourceIdentifier": "secure@microsoft.com",
  "vulnStatus": "Analyzed",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "NVD-CWE-Other"
        }
      ],
      "source": "nvd@nist.gov",
      "type": "Primary"
    }
  ]
}

GHSA-3F87-66X4-F3P7

Vulnerability from github – Published: 2022-05-24 19:20 – Updated: 2026-08-19 18:31

Details

Microsoft Exchange Server Remote Code Execution Vulnerability

Severity

8.8 (High)


                  
                    CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Show details on source website

JSON

To clipboard

{
  "affected": [],
  "aliases": [
    "CVE-2021-42321"
  ],
  "database_specific": {
    "cwe_ids": [],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2021-11-10T01:19:00Z",
    "severity": "HIGH"
  },
  "details": "Microsoft Exchange Server Remote Code Execution Vulnerability",
  "id": "GHSA-3f87-66x4-f3p7",
  "modified": "2026-08-19T18:31:43Z",
  "published": "2022-05-24T19:20:21Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2021-42321"
    },
    {
      "type": "WEB",
      "url": "https://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-42321"
    },
    {
      "type": "WEB",
      "url": "https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-42321"
    },
    {
      "type": "WEB",
      "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-42321"
    },
    {
      "type": "WEB",
      "url": "http://packetstormsecurity.com/files/166153/Microsoft-Exchange-Server-Remote-Code-Execution.html"
    },
    {
      "type": "WEB",
      "url": "http://packetstormsecurity.com/files/168131/Microsoft-Exchange-Server-ChainedSerializationBinder-Remote-Code-Execution.html"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ]
}

GSD-2021-42321

Vulnerability from gsd - Updated: 2023-12-13 01:23

Details

Microsoft Exchange Server Remote Code Execution Vulnerability

Aliases

CVE-2021-42321

Aliases

CVE-2021-42321

JSON

To clipboard

{
  "GSD": {
    "alias": "CVE-2021-42321",
    "description": "Microsoft Exchange Server Remote Code Execution Vulnerability",
    "id": "GSD-2021-42321",
    "references": [
      "https://packetstormsecurity.com/files/cve/CVE-2021-42321"
    ]
  },
  "gsd": {
    "metadata": {
      "exploitCode": "unknown",
      "remediation": "unknown",
      "reportConfidence": "confirmed",
      "type": "vulnerability"
    },
    "osvSchema": {
      "aliases": [
        "CVE-2021-42321"
      ],
      "details": "Microsoft Exchange Server Remote Code Execution Vulnerability",
      "id": "GSD-2021-42321",
      "modified": "2023-12-13T01:23:06.556780Z",
      "schema_version": "1.4.0"
    }
  },
  "namespaces": {
    "cisa.gov": {
      "cveID": "CVE-2021-42321",
      "dateAdded": "2021-11-17",
      "dueDate": "2021-12-01",
      "product": "Exchange",
      "requiredAction": "Apply updates per vendor instructions.",
      "shortDescription": "An authenticated attacker could leverage improper validation in cmdlet arguments within Microsoft Exchange and perform remote code execution.",
      "vendorProject": "Microsoft",
      "vulnerabilityName": "Microsoft Exchange Server Remote Code Execution Vulnerability"
    },
    "cve.org": {
      "CVE_data_meta": {
        "ASSIGNER": "secure@microsoft.com",
        "ID": "CVE-2021-42321",
        "STATE": "PUBLIC"
      },
      "affects": {
        "vendor": {
          "vendor_data": [
            {
              "product": {
                "product_data": [
                  {
                    "product_name": "Microsoft Exchange Server 2016 Cumulative Update 21",
                    "version": {
                      "version_data": [
                        {
                          "version_affected": "\u003c",
                          "version_name": "15.01.0",
                          "version_value": "15.01.2308.020"
                        }
                      ]
                    }
                  },
                  {
                    "product_name": "Microsoft Exchange Server 2019 Cumulative Update 10",
                    "version": {
                      "version_data": [
                        {
                          "version_affected": "\u003c",
                          "version_name": "15.02.0",
                          "version_value": "15.02.0792.019"
                        }
                      ]
                    }
                  },
                  {
                    "product_name": "Microsoft Exchange Server 2016 Cumulative Update 22",
                    "version": {
                      "version_data": [
                        {
                          "version_affected": "\u003c",
                          "version_name": "15.0.0",
                          "version_value": "15.01.2375.017"
                        }
                      ]
                    }
                  },
                  {
                    "product_name": "Microsoft Exchange Server 2019 Cumulative Update 11",
                    "version": {
                      "version_data": [
                        {
                          "version_affected": "\u003c",
                          "version_name": "15.02.0",
                          "version_value": "15.02.0986.014"
                        }
                      ]
                    }
                  }
                ]
              },
              "vendor_name": "Microsoft"
            }
          ]
        }
      },
      "data_format": "MITRE",
      "data_type": "CVE",
      "data_version": "4.0",
      "description": {
        "description_data": [
          {
            "lang": "eng",
            "value": "Microsoft Exchange Server Remote Code Execution Vulnerability"
          }
        ]
      },
      "impact": {
        "cvss": [
          {
            "baseScore": 8.8,
            "baseSeverity": "HIGH",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C",
            "version": "3.1"
          }
        ]
      },
      "problemtype": {
        "problemtype_data": [
          {
            "description": [
              {
                "lang": "eng",
                "value": "Remote Code Execution"
              }
            ]
          }
        ]
      },
      "references": {
        "reference_data": [
          {
            "name": "https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-42321",
            "refsource": "MISC",
            "url": "https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-42321"
          },
          {
            "name": "http://packetstormsecurity.com/files/166153/Microsoft-Exchange-Server-Remote-Code-Execution.html",
            "refsource": "MISC",
            "url": "http://packetstormsecurity.com/files/166153/Microsoft-Exchange-Server-Remote-Code-Execution.html"
          },
          {
            "name": "http://packetstormsecurity.com/files/168131/Microsoft-Exchange-Server-ChainedSerializationBinder-Remote-Code-Execution.html",
            "refsource": "MISC",
            "url": "http://packetstormsecurity.com/files/168131/Microsoft-Exchange-Server-ChainedSerializationBinder-Remote-Code-Execution.html"
          }
        ]
      }
    },
    "nvd.nist.gov": {
      "cve": {
        "cisaActionDue": "2021-12-01",
        "cisaExploitAdd": "2021-11-17",
        "cisaRequiredAction": "Apply updates per vendor instructions.",
        "cisaVulnerabilityName": "Microsoft Exchange Server Remote Code Execution Vulnerability",
        "configurations": [
          {
            "nodes": [
              {
                "cpeMatch": [
                  {
                    "criteria": "cpe:2.3:a:microsoft:exchange_server:2016:cumulative_update_21:*:*:*:*:*:*",
                    "matchCriteriaId": "3BE427A4-B0C2-4064-8234-29426325C348",
                    "vulnerable": true
                  },
                  {
                    "criteria": "cpe:2.3:a:microsoft:exchange_server:2016:cumulative_update_22:*:*:*:*:*:*",
                    "matchCriteriaId": "449CE85B-E599-44D3-A7C1-5133F6A55E86",
                    "vulnerable": true
                  },
                  {
                    "criteria": "cpe:2.3:a:microsoft:exchange_server:2019:cumulative_update_10:*:*:*:*:*:*",
                    "matchCriteriaId": "B4185347-EEDD-4239-9AB3-410E2EC89D2A",
                    "vulnerable": true
                  },
                  {
                    "criteria": "cpe:2.3:a:microsoft:exchange_server:2019:cumulative_update_11:*:*:*:*:*:*",
                    "matchCriteriaId": "435343A4-BF10-461A-ABF2-D511A5FBDA75",
                    "vulnerable": true
                  }
                ],
                "negate": false,
                "operator": "OR"
              }
            ]
          }
        ],
        "descriptions": [
          {
            "lang": "en",
            "value": "Microsoft Exchange Server Remote Code Execution Vulnerability"
          },
          {
            "lang": "es",
            "value": "Una vulnerabilidad de Ejecuci\u00f3n de C\u00f3digo Remota en Microsoft Exchange Server"
          }
        ],
        "id": "CVE-2021-42321",
        "lastModified": "2023-12-28T16:16:00.120",
        "metrics": {
          "cvssMetricV2": [
            {
              "acInsufInfo": false,
              "baseSeverity": "MEDIUM",
              "cvssData": {
                "accessComplexity": "LOW",
                "accessVector": "NETWORK",
                "authentication": "SINGLE",
                "availabilityImpact": "PARTIAL",
                "baseScore": 6.5,
                "confidentialityImpact": "PARTIAL",
                "integrityImpact": "PARTIAL",
                "vectorString": "AV:N/AC:L/Au:S/C:P/I:P/A:P",
                "version": "2.0"
              },
              "exploitabilityScore": 8.0,
              "impactScore": 6.4,
              "obtainAllPrivilege": false,
              "obtainOtherPrivilege": false,
              "obtainUserPrivilege": false,
              "source": "nvd@nist.gov",
              "type": "Primary",
              "userInteractionRequired": false
            }
          ],
          "cvssMetricV31": [
            {
              "cvssData": {
                "attackComplexity": "LOW",
                "attackVector": "NETWORK",
                "availabilityImpact": "HIGH",
                "baseScore": 8.8,
                "baseSeverity": "HIGH",
                "confidentialityImpact": "HIGH",
                "integrityImpact": "HIGH",
                "privilegesRequired": "LOW",
                "scope": "UNCHANGED",
                "userInteraction": "NONE",
                "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
                "version": "3.1"
              },
              "exploitabilityScore": 2.8,
              "impactScore": 5.9,
              "source": "secure@microsoft.com",
              "type": "Primary"
            },
            {
              "cvssData": {
                "attackComplexity": "LOW",
                "attackVector": "NETWORK",
                "availabilityImpact": "HIGH",
                "baseScore": 8.8,
                "baseSeverity": "HIGH",
                "confidentialityImpact": "HIGH",
                "integrityImpact": "HIGH",
                "privilegesRequired": "LOW",
                "scope": "UNCHANGED",
                "userInteraction": "NONE",
                "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
                "version": "3.1"
              },
              "exploitabilityScore": 2.8,
              "impactScore": 5.9,
              "source": "nvd@nist.gov",
              "type": "Secondary"
            }
          ]
        },
        "published": "2021-11-10T01:19:50.047",
        "references": [
          {
            "source": "secure@microsoft.com",
            "tags": [
              "Exploit",
              "Third Party Advisory",
              "VDB Entry"
            ],
            "url": "http://packetstormsecurity.com/files/166153/Microsoft-Exchange-Server-Remote-Code-Execution.html"
          },
          {
            "source": "secure@microsoft.com",
            "tags": [
              "Exploit",
              "Third Party Advisory",
              "VDB Entry"
            ],
            "url": "http://packetstormsecurity.com/files/168131/Microsoft-Exchange-Server-ChainedSerializationBinder-Remote-Code-Execution.html"
          },
          {
            "source": "secure@microsoft.com",
            "tags": [
              "Patch",
              "Vendor Advisory"
            ],
            "url": "https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-42321"
          }
        ],
        "sourceIdentifier": "secure@microsoft.com",
        "vulnStatus": "Modified",
        "weaknesses": [
          {
            "description": [
              {
                "lang": "en",
                "value": "NVD-CWE-Other"
              }
            ],
            "source": "nvd@nist.gov",
            "type": "Primary"
          }
        ]
      }
    }
  }
}

MSRC_CVE-2021-42321

Vulnerability from csaf_microsoft - Published: 2021-11-09 08:00 - Updated: 2022-06-21 07:00

Summary

Microsoft Exchange Server Remote Code Execution Vulnerability

Severity

Important

Scope

1 vulnerability in this advisory, including CVE-2021-42321.

CVE-2021-42321

8.8 (High)


                
                  CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C

Fixed: 4 products Known affected: 4 products

https://support.microsoft.com/help/5007409

Open the full advisory

Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.

Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.

Action not permitted

CVE-2021-42321 (GCVE-0-2021-42321)

CISA

Known Exploited Vulnerability - GCVE BCP-07 Compliant

Timestamps

Scope

Evidence

Vendor Report Successful Exploitation Confidence: 80% Source: cisa-kev

Details

References

Previdian

Known Exploited Vulnerability - GCVE BCP-07 Compliant

Timestamps

Scope

Evidence

Public Report Confirmed Compromise Confidence: 70% Source: kevintel

Details

References

BDU:2021-05330 (CVE-2021-42321)

CERTFR-2021-ALE-021

Solution

CERTFR-2021-AVI-863

Solution

CNVD-2021-90307

FKIE_CVE-2021-42321

GHSA-3F87-66X4-F3P7

GSD-2021-42321

MSRC_CVE-2021-42321

Tags

Sightings

Nomenclature

Related by attack behaviour