Vulnerability-Lookup

CVE-2021-31207 (GCVE-0-2021-31207)

Vulnerability from cvelistv5 – Published: 2021-05-11 19:11 – Updated: 2025-10-21 23:25

CISA Previdian

Title

Microsoft Exchange Server Security Feature Bypass Vulnerability

Summary

Microsoft Exchange Server Security Feature Bypass Vulnerability

Severity

6.6 (Medium)


                        
                          CVSS:3.1/AV:N/AC:H/PR:H/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 2025-02-04 18:16 UTC

CWE

Defense in Depth
CWE-434 - Unrestricted Upload of File with Dangerous Type

Assigner

microsoft mitre root

References

4 references

URL	Tags
https://portal.msrc.microsoft.com/en-US/security-…	x_refsource_MISC
https://www.zerodayinitiative.com/advisories/ZDI-…	x_refsource_MISC
http://packetstormsecurity.com/files/163895/Micro…	x_refsource_MISC
https://www.cisa.gov/known-exploited-vulnerabilit…	government-resource

Impacted products

5 products

Vendor	Product	Version
Microsoft	Microsoft Exchange Server 2013 Cumulative Update 23	Affected: 15.00.0 , < 15.00.1497.018 (custom) cpe:2.3:a:microsoft:exchange_server:2013:cumulative_update_23::::::
Microsoft	Microsoft Exchange Server 2019 Cumulative Update 9	Affected: 15.02.0 , < 15.02.0858.012 (custom) cpe:2.3:a:microsoft:exchange_server:2019:cumulative_update_9::::::
Microsoft	Microsoft Exchange Server 2016 Cumulative Update 20	Affected: 15.01.0 , < 15.01.2242.010 (custom) cpe:2.3:a:microsoft:exchange_server:2016:cumulative_update_20::::::
Microsoft	Microsoft Exchange Server 2016 Cumulative Update 19	Affected: 15.01.0 , < 15.01.2176.014 (custom) cpe:2.3:a:microsoft:exchange_server:2016:cumulative_update_19::::::
Microsoft	Microsoft Exchange Server 2019 Cumulative Update 8	Affected: 15.02.0 , < 15.02.0792.015 (custom) cpe:2.3:a:microsoft:exchange_server:2019:cumulative_update_8::::::

Date Public

2021-05-11 07:00

CISA

Known Exploited Vulnerability - GCVE BCP-07 Compliant

KEV entry ID: dcd55068-8a06-4994-b2ff-20e711611265

Vulnerability ID: CVE-2021-31207

Status: Confirmed

Status Updated: 2021-11-03 00:00 UTC

Exploited: Yes

Timestamps

First Seen: 2021-11-03

Asserted: 2021-11-03

Scope

Notes: KEV entry: Microsoft Exchange Server Security Feature Bypass Vulnerability | Affected: Microsoft / Exchange Server | Description: Microsoft Exchange Server contains an unspecified vulnerability that allows for security feature bypass. | Required action: Apply updates per vendor instructions. | Due date: 2021-11-17 | Known ransomware campaign use (KEV): Known | Notes (KEV): https://nvd.nist.gov/vuln/detail/CVE-2021-31207

Evidence

Type: Vendor Report

Signal: Successful Exploitation

Confidence: 80%

Source: cisa-kev

Details

Cwes	CWE-20 CWE-434
Feed	CISA Known Exploited Vulnerabilities Catalog
Product	Exchange Server
Due Date	2021-11-17
Date Added	2021-11-03
Vendorproject	Microsoft
Vulnerabilityname	Microsoft Exchange Server Security Feature Bypass Vulnerability
Knownransomwarecampaignuse	Known

References

CVE-2021-31207

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: 66a4179e-fbfc-4815-a99a-93fb1fec1d6b

Vulnerability ID: CVE-2021-31207

Status: Confirmed

Status Updated: 2021-11-03 00:00 UTC

Exploited: Yes

Timestamps

First Seen: 2021-11-03

Asserted: 2021-11-03

Scope

Notes: KEVIntel entry: Microsoft Exchange Server Security Feature Bypass Vulnerability | Affected: Microsoft / Microsoft Exchange Server 2013 Cumulative Update 23, Microsoft Exchange Server 2019 Cumulative Update 9, Microsoft Exchange Server 2016 Cumulative Update 20, Microsoft Exchange Server 2016 Cumulative Update 19, Microsoft Exchange Server 2019 Cumulative Update 8 | CVSS: 6.6 (MEDIUM) | 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 Security Feature Bypass Vulnerability
Vendor	Microsoft
Product	Microsoft Exchange Server 2013 Cumulative Update 23, Microsoft Exchange Server 2019 Cumulative Update 9, Microsoft Exchange Server 2016 Cumulative Update 20, Microsoft Exchange Server 2016 Cumulative Update 19, Microsoft Exchange Server 2019 Cumulative Update 8
Added Date	2021-11-03T00:00:00.000Z
Cvss Score	6.6
Epss Score	None
Cvss Severity	MEDIUM
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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                "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-31207"
              }
            ],
            "timeline": [
              {
                "lang": "en",
                "time": "2021-11-03T00:00:00.000Z",
                "value": "CVE-2021-31207 added to CISA KEV"
              }
            ],
            "title": "CISA ADP Vulnrichment"
          }
        ],
        "cna": {
          "affected": [
            {
              "cpes": [
                "cpe:2.3:a:microsoft:exchange_server:2013:cumulative_update_23:*:*:*:*:*:*"
              ],
              "platforms": [
                "x64-based Systems"
              ],
              "product": "Microsoft Exchange Server 2013 Cumulative Update 23",
              "vendor": "Microsoft",
              "versions": [
                {
                  "lessThan": "15.00.1497.018",
                  "status": "affected",
                  "version": "15.00.0",
                  "versionType": "custom"
                }
              ]
            },
            {
              "cpes": [
                "cpe:2.3:a:microsoft:exchange_server:2019:cumulative_update_9:*:*:*:*:*:*"
              ],
              "platforms": [
                "x64-based Systems"
              ],
              "product": "Microsoft Exchange Server 2019 Cumulative Update 9",
              "vendor": "Microsoft",
              "versions": [
                {
                  "lessThan": "15.02.0858.012",
                  "status": "affected",
                  "version": "15.02.0",
                  "versionType": "custom"
                }
              ]
            },
            {
              "cpes": [
                "cpe:2.3:a:microsoft:exchange_server:2016:cumulative_update_20:*:*:*:*:*:*"
              ],
              "platforms": [
                "x64-based Systems"
              ],
              "product": "Microsoft Exchange Server 2016 Cumulative Update 20",
              "vendor": "Microsoft",
              "versions": [
                {
                  "lessThan": "15.01.2242.010",
                  "status": "affected",
                  "version": "15.01.0",
                  "versionType": "custom"
                }
              ]
            },
            {
              "cpes": [
                "cpe:2.3:a:microsoft:exchange_server:2016:cumulative_update_19:*:*:*:*:*:*"
              ],
              "platforms": [
                "x64-based Systems"
              ],
              "product": "Microsoft Exchange Server 2016 Cumulative Update 19",
              "vendor": "Microsoft",
              "versions": [
                {
                  "lessThan": "15.01.2176.014",
                  "status": "affected",
                  "version": "15.01.0",
                  "versionType": "custom"
                }
              ]
            },
            {
              "cpes": [
                "cpe:2.3:a:microsoft:exchange_server:2019:cumulative_update_8:*:*:*:*:*:*"
              ],
              "platforms": [
                "x64-based Systems"
              ],
              "product": "Microsoft Exchange Server 2019 Cumulative Update 8",
              "vendor": "Microsoft",
              "versions": [
                {
                  "lessThan": "15.02.0792.015",
                  "status": "affected",
                  "version": "15.02.0",
                  "versionType": "custom"
                }
              ]
            }
          ],
          "datePublic": "2021-05-11T07:00:00.000Z",
          "descriptions": [
            {
              "lang": "en-US",
              "value": "Microsoft Exchange Server Security Feature Bypass Vulnerability"
            }
          ],
          "metrics": [
            {
              "cvssV3_1": {
                "baseScore": 6.6,
                "baseSeverity": "MEDIUM",
                "vectorString": "CVSS:3.1/AV:N/AC:H/PR:H/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": "Defense in Depth",
                  "lang": "en-US",
                  "type": "Impact"
                }
              ]
            }
          ],
          "providerMetadata": {
            "dateUpdated": "2023-12-28T23:57:04.957Z",
            "orgId": "f38d906d-7342-40ea-92c1-6c4a2c6478c8",
            "shortName": "microsoft"
          },
          "references": [
            {
              "tags": [
                "x_refsource_MISC"
              ],
              "url": "https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-31207"
            },
            {
              "tags": [
                "x_refsource_MISC"
              ],
              "url": "https://www.zerodayinitiative.com/advisories/ZDI-21-819/"
            },
            {
              "tags": [
                "x_refsource_MISC"
              ],
              "url": "http://packetstormsecurity.com/files/163895/Microsoft-Exchange-ProxyShell-Remote-Code-Execution.html"
            }
          ],
          "title": "Microsoft Exchange Server Security Feature Bypass Vulnerability"
        }
      },
      "cveMetadata": {
        "assignerOrgId": "f38d906d-7342-40ea-92c1-6c4a2c6478c8",
        "assignerShortName": "microsoft",
        "cveId": "CVE-2021-31207",
        "datePublished": "2021-05-11T19:11:41.000Z",
        "dateReserved": "2021-04-14T00:00:00.000Z",
        "dateUpdated": "2025-10-21T23:25:45.697Z",
        "state": "PUBLISHED"
      },
      "dataType": "CVE_RECORD",
      "dataVersion": "5.1"
    }
  }
}

BDU:2021-02608 (CVE-2021-31207)

Vulnerability from fstec – Published: 2021-05-20 – Updated: 2026-05-18 – View on bdu.fstec.ru Exploit publicly available Yes Fixed

CISA Previdian

Title

Уязвимость почтового сервера Microsoft Exchange Server, связанная с ошибками в настройках безопасности, позволяющая нарушителю выполнить произвольный код с привилегиями SYSTEM

Summary

Уязвимость почтового сервера Microsoft Exchange Server связана с ошибками в настройках безопасности. Эксплуатация уязвимости может позволить нарушителю, действующему удаленно, выполнить произвольный код с привилегиями SYSTEM

Severity

7.6 (High) CVSS 2.0


                      
                        AV:N/AC:H/Au:N/C:C/I:C/A:C

6.6 (Medium) CVSS 3.0


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

Class

Architecture vulnerability

Status

Confirmed by the vendor

Exploitation

Functionality abuse

Incidents

Yes

Remediation

Software update

CWE

CWE-254 - Элементы безопасности

Aliases

CVE-2021-31207, ZDI-21-819

References

6 references

URL
https://msrc.microsoft.com/update-guide/en-US/vulnerability/CVE-2021-31207
https://nvd.nist.gov/vuln/detail/CVE-2021-31207
https://www.cybersecurity-help.cz/vdb/SB2021051112
https://www.zerodayinitiative.com/advisories/ZDI-21-819/
https://www.cisa.gov/sites/default/files/csv/known_exploited_vulnerabilities.csv
http://packetstormsecurity.com/files/163895/Microsoft-Exchange-ProxyShell-Remot…

Impacted products

1 product from 1 vendor

Vendors

Microsoft Corp

Products

Microsoft Exchange Server

Versions

2016 Cumulative Update 19 (Microsoft Exchange Server), 2013 Cumulative Update 23 (Microsoft Exchange Server), 2019 Cumulative Update 8 (Microsoft Exchange Server), 2019 Cumulative Update 9 (Microsoft Exchange Server), 2016 Cumulative Update 20 (Microsoft Exchange Server)

Product types

Application software

Mitigations

Использование рекомендаций: https://msrc.microsoft.com/update-guide/en-US/vulnerability/CVE-2021-31207

JSON

To clipboard

{
  "CVSS 2.0": "AV:N/AC:H/Au:N/C:C/I:C/A:C",
  "CVSS 3.0": "AV:N/AC:H/PR:H/UI:N/S:U/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": "2016 Cumulative Update 19 (Microsoft Exchange Server), 2013 Cumulative Update 23 (Microsoft Exchange Server), 2019 Cumulative Update 8 (Microsoft Exchange Server), 2019 Cumulative Update 9 (Microsoft Exchange Server), 2016 Cumulative Update 20 (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/en-US/vulnerability/CVE-2021-31207",
  "\u0414\u0430\u0442\u0430 \u0432\u044b\u044f\u0432\u043b\u0435\u043d\u0438\u044f": "11.05.2021",
  "\u0414\u0430\u0442\u0430 \u043f\u043e\u0441\u043b\u0435\u0434\u043d\u0435\u0433\u043e \u043e\u0431\u043d\u043e\u0432\u043b\u0435\u043d\u0438\u044f": "18.05.2026",
  "\u0414\u0430\u0442\u0430 \u043f\u0443\u0431\u043b\u0438\u043a\u0430\u0446\u0438\u0438": "20.05.2021",
  "\u0418\u0434\u0435\u043d\u0442\u0438\u0444\u0438\u043a\u0430\u0442\u043e\u0440": "BDU:2021-02608",
  "\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-2021-31207, ZDI-21-819",
  "\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 \u0430\u0440\u0445\u0438\u0442\u0435\u043a\u0442\u0443\u0440\u044b",
  "\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 \u043e\u0448\u0438\u0431\u043a\u0430\u043c\u0438 \u0432 \u043d\u0430\u0441\u0442\u0440\u043e\u0439\u043a\u0430\u0445 \u0431\u0435\u0437\u043e\u043f\u0430\u0441\u043d\u043e\u0441\u0442\u0438, \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 \u0441 \u043f\u0440\u0438\u0432\u0438\u043b\u0435\u0433\u0438\u044f\u043c\u0438 SYSTEM",
  "\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": "\u042d\u043b\u0435\u043c\u0435\u043d\u0442\u044b \u0431\u0435\u0437\u043e\u043f\u0430\u0441\u043d\u043e\u0441\u0442\u0438 (CWE-254)",
  "\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 \u043e\u0448\u0438\u0431\u043a\u0430\u043c\u0438 \u0432 \u043d\u0430\u0441\u0442\u0440\u043e\u0439\u043a\u0430\u0445 \u0431\u0435\u0437\u043e\u043f\u0430\u0441\u043d\u043e\u0441\u0442\u0438. \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 \u0441 \u043f\u0440\u0438\u0432\u0438\u043b\u0435\u0433\u0438\u044f\u043c\u0438 SYSTEM",
  "\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": "\u0417\u043b\u043e\u0443\u043f\u043e\u0442\u0440\u0435\u0431\u043b\u0435\u043d\u0438\u0435 \u0444\u0443\u043d\u043a\u0446\u0438\u043e\u043d\u0430\u043b\u043e\u043c",
  "\u0421\u0441\u044b\u043b\u043a\u0438 \u043d\u0430 \u0438\u0441\u0442\u043e\u0447\u043d\u0438\u043a\u0438": "https://msrc.microsoft.com/update-guide/en-US/vulnerability/CVE-2021-31207\nhttps://nvd.nist.gov/vuln/detail/CVE-2021-31207\nhttps://www.cybersecurity-help.cz/vdb/SB2021051112\nhttps://www.zerodayinitiative.com/advisories/ZDI-21-819/\nhttps://www.cisa.gov/sites/default/files/csv/known_exploited_vulnerabilities.csv\nhttp://packetstormsecurity.com/files/163895/Microsoft-Exchange-ProxyShell-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-254",
  "\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 7,6)\n\u0421\u0440\u0435\u0434\u043d\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 6,6)"
}

CERTFR-2021-ALE-017

Vulnerability from certfr_alerte - Published: 2021-08-27 - Updated: 2022-05-04

Dans son bulletin d'actualité CERTFR-2021-ACT-035 du 12 août 2021 [1], le CERT-FR revenait sur la publication d'une technique permettant de prendre le contrôle d'un serveur Microsoft Exchange. La technique, dénommée "ProxyShell" s'appuie sur l'existence de plusieurs vulnérabilités corrigées en avril et en mai 2021 [4] (mais annoncées en juillet) [2] [3].

Récemment, le CERT-FR a pris connaissance d'activités malveillantes qui pourraient-être basées sur une exploitation de ces vulnérabilités et ciblant les serveurs Microsoft Exchange d'entités françaises.

Le CERT-FR a signalé l'existence de serveurs vulnérables exposés sur Internet à leurs propriétaires, mais sans possibilité d'exhaustivité. Par conséquent le CERT-FR rappelle les recommandations suivantes :

appliquer immédiatement les correctifs de sécurité fournis par l’éditeur sur l’ensemble des serveurs Exchange vulnérables exposés sur Internet puis en interne ;
procéder à l’analyse des serveurs Exchange afin d’identifier une possible activité anormale à l'aide des informations fournies dans notre bulletin CERTFR-2021-ACT-035 et la présence de webshells ;
en cas de compromission, contrôler le système d’information pour détecter d’éventuelles latéralisations ainsi qu’une compromission des serveurs Active Directory.

Enfin, le CERT-FR rappelle que les serveurs Microsoft Exchange ne devraient pas être exposés sans protection sur Internet. Il est fortement recommandé d’appliquer les bonnes pratiques publiées par l’ANSSI pour ce type service [5].

Solution

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

Impacted products

	Vendor	Product	Description

References

Title

Publication Time

CERTFR-2021-AVI-369

Vulnerability from certfr_avis - Published: 2021-05-12 - Updated: 2021-05-12

De multiples vulnérabilités ont été corrigées dans les produits Microsoft. Elles permettent à un attaquant de provoquer une élévation de privilèges, une exécution de code à distance, une atteinte à la confidentialité des données, une usurpation d'identité 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	Skype pour Business Server 2019 CU5
Microsoft	N/A	Microsoft Visual Studio 2019 version 16.7 (includes 16.0 – 16.6)
Microsoft	N/A	Microsoft Exchange Server 2016 Cumulative Update 19
Microsoft	N/A	Microsoft Visual Studio 2019 version 16.9 (includes 16.0 - 16.8)
Microsoft	N/A	Dynamics 365 pour Finance and Operations
Microsoft	N/A	Microsoft Exchange Server 2019 Cumulative Update 8
Microsoft	N/A	common_utils.py
Microsoft	N/A	Microsoft Visual Studio 2019 version 16.4 (includes 16.0 - 16.3)
Microsoft	N/A	Visual Studio Code
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	Skype pour Business Server 2015 CU11
Microsoft	N/A	Microsoft Exchange Server 2016 Cumulative Update 20
Microsoft	N/A	Microsoft Exchange Server 2019 Cumulative Update 9
Microsoft	N/A	Visual Studio 2019 pour Mac version 8.9
Microsoft	N/A	Microsoft Lync Server 2013 CU10
Microsoft	N/A	Visual Studio Code Remote - Containers Extension
Microsoft	N/A	Web Media Extensions

References

Title

Publication Time

FKIE_CVE-2021-31207

Vulnerability from fkie_nvd - Published: 2021-05-11 19:15 - Updated: 2026-06-17 03:51

CISA Previdian

Severity

6.6 (Medium) - CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:H/I:H/A:H
6.6 (Medium) - CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:H/I:H/A:H

Summary

Microsoft Exchange Server Security Feature Bypass Vulnerability

References

URL	Tags
secure@microsoft.com	http://packetstormsecurity.com/files/163895/Microsoft-Exchange-ProxyShell-Remote-Code-Execution.html	Exploit, Third Party Advisory, VDB Entry
secure@microsoft.com	https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-31207	Patch, Vendor Advisory
secure@microsoft.com	https://www.zerodayinitiative.com/advisories/ZDI-21-819/	Third Party Advisory, VDB Entry
af854a3a-2127-422b-91ae-364da2661108	http://packetstormsecurity.com/files/163895/Microsoft-Exchange-ProxyShell-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-2021-31207	Patch, Vendor Advisory
af854a3a-2127-422b-91ae-364da2661108	https://www.zerodayinitiative.com/advisories/ZDI-21-819/	Third Party Advisory, VDB Entry
134c704f-9b21-4f2e-91b3-4a467353bcc0	https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-31207	US Government Resource

Impacted products

Vendor	Product	Version
microsoft	exchange_server	2013
microsoft	exchange_server	2016
microsoft	exchange_server	2016
microsoft	exchange_server	2019
microsoft	exchange_server	2019

JSON

To clipboard

{
  "affected": [
    {
      "affectedData": [
        {
          "cpes": [
            "cpe:2.3:a:microsoft:exchange_server:2013:cumulative_update_23:*:*:*:*:*:*"
          ],
          "platforms": [
            "x64-based Systems"
          ],
          "product": "Microsoft Exchange Server 2013 Cumulative Update 23",
          "vendor": "Microsoft",
          "versions": [
            {
              "lessThan": "15.00.1497.018",
              "status": "affected",
              "version": "15.00.0",
              "versionType": "custom"
            }
          ]
        },
        {
          "cpes": [
            "cpe:2.3:a:microsoft:exchange_server:2019:cumulative_update_9:*:*:*:*:*:*"
          ],
          "platforms": [
            "x64-based Systems"
          ],
          "product": "Microsoft Exchange Server 2019 Cumulative Update 9",
          "vendor": "Microsoft",
          "versions": [
            {
              "lessThan": "15.02.0858.012",
              "status": "affected",
              "version": "15.02.0",
              "versionType": "custom"
            }
          ]
        },
        {
          "cpes": [
            "cpe:2.3:a:microsoft:exchange_server:2016:cumulative_update_20:*:*:*:*:*:*"
          ],
          "platforms": [
            "x64-based Systems"
          ],
          "product": "Microsoft Exchange Server 2016 Cumulative Update 20",
          "vendor": "Microsoft",
          "versions": [
            {
              "lessThan": "15.01.2242.010",
              "status": "affected",
              "version": "15.01.0",
              "versionType": "custom"
            }
          ]
        },
        {
          "cpes": [
            "cpe:2.3:a:microsoft:exchange_server:2016:cumulative_update_19:*:*:*:*:*:*"
          ],
          "platforms": [
            "x64-based Systems"
          ],
          "product": "Microsoft Exchange Server 2016 Cumulative Update 19",
          "vendor": "Microsoft",
          "versions": [
            {
              "lessThan": "15.01.2176.014",
              "status": "affected",
              "version": "15.01.0",
              "versionType": "custom"
            }
          ]
        },
        {
          "cpes": [
            "cpe:2.3:a:microsoft:exchange_server:2019:cumulative_update_8:*:*:*:*:*:*"
          ],
          "platforms": [
            "x64-based Systems"
          ],
          "product": "Microsoft Exchange Server 2019 Cumulative Update 8",
          "vendor": "Microsoft",
          "versions": [
            {
              "lessThan": "15.02.0792.015",
              "status": "affected",
              "version": "15.02.0",
              "versionType": "custom"
            }
          ]
        }
      ],
      "source": "secure@microsoft.com"
    }
  ],
  "cisaActionDue": "2021-11-17",
  "cisaExploitAdd": "2021-11-03",
  "cisaRequiredAction": "Apply updates per vendor instructions.",
  "cisaVulnerabilityName": "Microsoft Exchange Server Security Feature Bypass Vulnerability",
  "configurations": [
    {
      "nodes": [
        {
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:a:microsoft:exchange_server:2013:cumulative_update_23:*:*:*:*:*:*",
              "matchCriteriaId": "DA166F2A-D83B-4D50-AD0B-668D813E0585",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:a:microsoft:exchange_server:2016:cumulative_update_19:*:*:*:*:*:*",
              "matchCriteriaId": "28FCA0E8-7D27-4746-9731-91B834CA3E64",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:a:microsoft:exchange_server:2016:cumulative_update_20:*:*:*:*:*:*",
              "matchCriteriaId": "19C1EE0C-B8DD-4B91-BE4B-1C42D72FB718",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:a:microsoft:exchange_server:2019:cumulative_update_8:*:*:*:*:*:*",
              "matchCriteriaId": "44ECF39A-1DE1-4870-A494-06A53494338D",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:a:microsoft:exchange_server:2019:cumulative_update_9:*:*:*:*:*:*",
              "matchCriteriaId": "71CDF29B-116B-4DE2-AFD0-B62477FF0AEB",
              "vulnerable": true
            }
          ],
          "negate": false,
          "operator": "OR"
        }
      ]
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "Microsoft Exchange Server Security Feature Bypass Vulnerability"
    },
    {
      "lang": "es",
      "value": "Una vulnerabilidad de Omisi\u00f3n de la Caracter\u00edstica de Seguridad de Microsoft Exchange Server"
    }
  ],
  "id": "CVE-2021-31207",
  "lastModified": "2026-06-17T03:51:27.123",
  "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": "HIGH",
          "attackVector": "NETWORK",
          "availabilityImpact": "HIGH",
          "baseScore": 6.6,
          "baseSeverity": "MEDIUM",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "privilegesRequired": "HIGH",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:H/I:H/A:H",
          "version": "3.1"
        },
        "exploitabilityScore": 0.7,
        "impactScore": 5.9,
        "source": "secure@microsoft.com",
        "type": "Secondary"
      },
      {
        "cvssData": {
          "attackComplexity": "HIGH",
          "attackVector": "NETWORK",
          "availabilityImpact": "HIGH",
          "baseScore": 6.6,
          "baseSeverity": "MEDIUM",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "privilegesRequired": "HIGH",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:H/I:H/A:H",
          "version": "3.1"
        },
        "exploitabilityScore": 0.7,
        "impactScore": 5.9,
        "source": "nvd@nist.gov",
        "type": "Secondary"
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2021-31207",
          "options": [
            {
              "exploitation": "active"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "total"
            }
          ],
          "role": "CISA Coordinator",
          "timestamp": "2025-02-04T18:16:59.637651Z",
          "version": "2.0.3"
        }
      }
    ]
  },
  "published": "2021-05-11T19:15:10.397",
  "references": [
    {
      "source": "secure@microsoft.com",
      "tags": [
        "Exploit",
        "Third Party Advisory",
        "VDB Entry"
      ],
      "url": "http://packetstormsecurity.com/files/163895/Microsoft-Exchange-ProxyShell-Remote-Code-Execution.html"
    },
    {
      "source": "secure@microsoft.com",
      "tags": [
        "Patch",
        "Vendor Advisory"
      ],
      "url": "https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-31207"
    },
    {
      "source": "secure@microsoft.com",
      "tags": [
        "Third Party Advisory",
        "VDB Entry"
      ],
      "url": "https://www.zerodayinitiative.com/advisories/ZDI-21-819/"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "tags": [
        "Exploit",
        "Third Party Advisory",
        "VDB Entry"
      ],
      "url": "http://packetstormsecurity.com/files/163895/Microsoft-Exchange-ProxyShell-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-2021-31207"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "tags": [
        "Third Party Advisory",
        "VDB Entry"
      ],
      "url": "https://www.zerodayinitiative.com/advisories/ZDI-21-819/"
    },
    {
      "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
      "tags": [
        "US Government Resource"
      ],
      "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-31207"
    }
  ],
  "sourceIdentifier": "secure@microsoft.com",
  "vulnStatus": "Analyzed",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-434"
        }
      ],
      "source": "nvd@nist.gov",
      "type": "Primary"
    },
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-434"
        }
      ],
      "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
      "type": "Secondary"
    }
  ]
}

GHSA-JCXV-6F65-7HRX

Vulnerability from github – Published: 2022-05-24 19:01 – Updated: 2025-10-22 00:32

Details

Microsoft Exchange Server Security Feature Bypass Vulnerability

Severity

7.2 (High)


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

Show details on source website

JSON

To clipboard

{
  "affected": [],
  "aliases": [
    "CVE-2021-31207"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-22",
      "CWE-434"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2021-05-11T19:15:00Z",
    "severity": "HIGH"
  },
  "details": "Microsoft Exchange Server Security Feature Bypass Vulnerability",
  "id": "GHSA-jcxv-6f65-7hrx",
  "modified": "2025-10-22T00:32:13Z",
  "published": "2022-05-24T19:01:59Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2021-31207"
    },
    {
      "type": "WEB",
      "url": "https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-31207"
    },
    {
      "type": "WEB",
      "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-31207"
    },
    {
      "type": "WEB",
      "url": "https://www.zerodayinitiative.com/advisories/ZDI-21-819"
    },
    {
      "type": "WEB",
      "url": "http://packetstormsecurity.com/files/163895/Microsoft-Exchange-ProxyShell-Remote-Code-Execution.html"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ]
}

GSD-2021-31207

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

Details

Microsoft Exchange Server Security Feature Bypass Vulnerability

Aliases

CVE-2021-31207

Aliases

CVE-2021-31207

JSON

To clipboard

{
  "GSD": {
    "alias": "CVE-2021-31207",
    "description": "Microsoft Exchange Server Security Feature Bypass Vulnerability",
    "id": "GSD-2021-31207",
    "references": [
      "https://packetstormsecurity.com/files/cve/CVE-2021-31207"
    ]
  },
  "gsd": {
    "metadata": {
      "exploitCode": "unknown",
      "remediation": "unknown",
      "reportConfidence": "confirmed",
      "type": "vulnerability"
    },
    "osvSchema": {
      "aliases": [
        "CVE-2021-31207"
      ],
      "details": "Microsoft Exchange Server Security Feature Bypass Vulnerability",
      "id": "GSD-2021-31207",
      "modified": "2023-12-13T01:23:13.397576Z",
      "schema_version": "1.4.0"
    }
  },
  "namespaces": {
    "cisa.gov": {
      "cveID": "CVE-2021-31207",
      "dateAdded": "2021-11-03",
      "dueDate": "2021-11-17",
      "product": "Microsoft Exchange Server",
      "requiredAction": "Apply updates per vendor instructions.",
      "shortDescription": "Microsoft Exchange Server Security Feature Bypass Vulnerability",
      "vendorProject": "Microsoft",
      "vulnerabilityName": "Microsoft Exchange Server Security Feature Bypass Vulnerability"
    },
    "cve.org": {
      "CVE_data_meta": {
        "ASSIGNER": "secure@microsoft.com",
        "ID": "CVE-2021-31207",
        "STATE": "PUBLIC"
      },
      "affects": {
        "vendor": {
          "vendor_data": [
            {
              "product": {
                "product_data": [
                  {
                    "product_name": "Microsoft Exchange Server 2013 Cumulative Update 23",
                    "version": {
                      "version_data": [
                        {
                          "version_affected": "\u003c",
                          "version_name": "15.00.0",
                          "version_value": "15.00.1497.018"
                        }
                      ]
                    }
                  },
                  {
                    "product_name": "Microsoft Exchange Server 2019 Cumulative Update 9",
                    "version": {
                      "version_data": [
                        {
                          "version_affected": "\u003c",
                          "version_name": "15.02.0",
                          "version_value": "15.02.0858.012"
                        }
                      ]
                    }
                  },
                  {
                    "product_name": "Microsoft Exchange Server 2016 Cumulative Update 20",
                    "version": {
                      "version_data": [
                        {
                          "version_affected": "\u003c",
                          "version_name": "15.01.0",
                          "version_value": "15.01.2242.010"
                        }
                      ]
                    }
                  },
                  {
                    "product_name": "Microsoft Exchange Server 2016 Cumulative Update 19",
                    "version": {
                      "version_data": [
                        {
                          "version_affected": "\u003c",
                          "version_name": "15.01.0",
                          "version_value": "15.01.2176.014"
                        }
                      ]
                    }
                  },
                  {
                    "product_name": "Microsoft Exchange Server 2019 Cumulative Update 8",
                    "version": {
                      "version_data": [
                        {
                          "version_affected": "\u003c",
                          "version_name": "15.02.0",
                          "version_value": "15.02.0792.015"
                        }
                      ]
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            }
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      },
      "impact": {
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          {
            "baseScore": 6.6,
            "baseSeverity": "MEDIUM",
            "vectorString": "CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C",
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          }
        ]
      },
      "problemtype": {
        "problemtype_data": [
          {
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              {
                "lang": "eng",
                "value": "Defense in Depth"
              }
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        ]
      },
      "references": {
        "reference_data": [
          {
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            "refsource": "MISC",
            "url": "https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-31207"
          },
          {
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            "refsource": "MISC",
            "url": "https://www.zerodayinitiative.com/advisories/ZDI-21-819/"
          },
          {
            "name": "http://packetstormsecurity.com/files/163895/Microsoft-Exchange-ProxyShell-Remote-Code-Execution.html",
            "refsource": "MISC",
            "url": "http://packetstormsecurity.com/files/163895/Microsoft-Exchange-ProxyShell-Remote-Code-Execution.html"
          }
        ]
      }
    },
    "nvd.nist.gov": {
      "configurations": {
        "CVE_data_version": "4.0",
        "nodes": [
          {
            "children": [],
            "cpe_match": [
              {
                "cpe23Uri": "cpe:2.3:a:microsoft:exchange_server:2013:cumulative_update_23:*:*:*:*:*:*",
                "cpe_name": [],
                "vulnerable": true
              },
              {
                "cpe23Uri": "cpe:2.3:a:microsoft:exchange_server:2019:cumulative_update_8:*:*:*:*:*:*",
                "cpe_name": [],
                "vulnerable": true
              },
              {
                "cpe23Uri": "cpe:2.3:a:microsoft:exchange_server:2016:cumulative_update_19:*:*:*:*:*:*",
                "cpe_name": [],
                "vulnerable": true
              },
              {
                "cpe23Uri": "cpe:2.3:a:microsoft:exchange_server:2016:cumulative_update_20:*:*:*:*:*:*",
                "cpe_name": [],
                "vulnerable": true
              },
              {
                "cpe23Uri": "cpe:2.3:a:microsoft:exchange_server:2019:cumulative_update_9:*:*:*:*:*:*",
                "cpe_name": [],
                "vulnerable": true
              }
            ],
            "operator": "OR"
          }
        ]
      },
      "cve": {
        "CVE_data_meta": {
          "ASSIGNER": "secure@microsoft.com",
          "ID": "CVE-2021-31207"
        },
        "data_format": "MITRE",
        "data_type": "CVE",
        "data_version": "4.0",
        "description": {
          "description_data": [
            {
              "lang": "en",
              "value": "Microsoft Exchange Server Security Feature Bypass Vulnerability"
            }
          ]
        },
        "problemtype": {
          "problemtype_data": [
            {
              "description": [
                {
                  "lang": "en",
                  "value": "CWE-22"
                }
              ]
            }
          ]
        },
        "references": {
          "reference_data": [
            {
              "name": "N/A",
              "refsource": "N/A",
              "tags": [
                "Patch",
                "Vendor Advisory"
              ],
              "url": "https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-31207"
            },
            {
              "name": "https://www.zerodayinitiative.com/advisories/ZDI-21-819/",
              "refsource": "MISC",
              "tags": [
                "Third Party Advisory",
                "VDB Entry"
              ],
              "url": "https://www.zerodayinitiative.com/advisories/ZDI-21-819/"
            },
            {
              "name": "http://packetstormsecurity.com/files/163895/Microsoft-Exchange-ProxyShell-Remote-Code-Execution.html",
              "refsource": "MISC",
              "tags": [
                "Exploit",
                "Third Party Advisory",
                "VDB Entry"
              ],
              "url": "http://packetstormsecurity.com/files/163895/Microsoft-Exchange-ProxyShell-Remote-Code-Execution.html"
            }
          ]
        }
      },
      "impact": {
        "baseMetricV2": {
          "acInsufInfo": false,
          "cvssV2": {
            "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,
          "severity": "MEDIUM",
          "userInteractionRequired": false
        },
        "baseMetricV3": {
          "cvssV3": {
            "attackComplexity": "HIGH",
            "attackVector": "NETWORK",
            "availabilityImpact": "HIGH",
            "baseScore": 6.6,
            "baseSeverity": "MEDIUM",
            "confidentialityImpact": "HIGH",
            "integrityImpact": "HIGH",
            "privilegesRequired": "HIGH",
            "scope": "UNCHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:H/I:H/A:H",
            "version": "3.1"
          },
          "exploitabilityScore": 0.7,
          "impactScore": 5.9
        }
      },
      "lastModifiedDate": "2023-08-02T00:15Z",
      "publishedDate": "2021-05-11T19:15Z"
    }
  }
}

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-2021-31207 (GCVE-0-2021-31207)

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:2021-02608 (CVE-2021-31207)

CERTFR-2021-ALE-017

Solution

CERTFR-2021-AVI-369

Solution

FKIE_CVE-2021-31207

GHSA-JCXV-6F65-7HRX

GSD-2021-31207

Tags

Sightings

Nomenclature

Related by attack behaviour