CVE-2021-31207 - OpenCVE

Microsoft Exchange Server Security Feature Bypass Vulnerability

No CVSS v4.0

Attack Vector Network

Attack Complexity High

Privileges Required High

Scope Unchanged

Confidentiality Impact High

Integrity Impact High

Availability Impact High

User Interaction None

No CVSS v3.0

Access Vector Network

Access Complexity Low

Authentication Single

Confidentiality Impact Partial

Integrity Impact Partial

Availability Impact Partial

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

This CVE is in the KEV database since Nov. 3, 2021.

Exploitation active

Automatable no

Technical Impact total

Vendors	Products
Microsoft	Exchange Server

Configuration 1 [-]

OR	cpe:2.3:a:microsoft:exchange_server:2013:cumulative_update_23::::::
	cpe:2.3:a:microsoft:exchange_server:2016:cumulative_update_19::::::
	cpe:2.3:a:microsoft:exchange_server:2016:cumulative_update_20::::::
	cpe:2.3:a:microsoft:exchange_server:2019:cumulative_update_8::::::
	cpe:2.3:a:microsoft:exchange_server:2019:cumulative_update_9::::::

No data.

References

Link	Providers
http://packetstormsecurity.com/files/163895/Microsoft-Exchange-ProxyShell-Remote-Code-Execution.html
https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-31207
https://www.zerodayinitiative.com/advisories/ZDI-21-819/

History

Wed, 16 Jul 2025 13:45:00 +0000

Type	Values Removed	Values Added
Metrics	epss `{'score': 0.94028}`	epss `{'score': 0.94004}`

Tue, 15 Jul 2025 13:45:00 +0000

Type	Values Removed	Values Added
Metrics	epss `{'score': 0.93866}`	epss `{'score': 0.94028}`

Tue, 04 Feb 2025 19:15:00 +0000

Type	Values Removed	Values Added
Metrics		kev `{'dateAdded': '2021-11-03'}` ssvc `{'options': {'Automatable': 'no', 'Exploitation': 'active', 'Technical Impact': 'total'}, 'version': '2.0.3'}`

MITRE

Status: PUBLISHED

Assigner: microsoft

Published: 2021-05-11T19:11:41.000Z

Updated: 2025-07-30T01:38:10.562Z

Reserved: 2021-04-14T00:00:00.000Z

Link: CVE-2021-31207

Vulnrichment

Updated: 2024-08-03T22:55:53.519Z

NVD

Status : Analyzed

Published: 2021-05-11T19:15:10.397

Modified: 2025-03-13T16:41:49.303

Link: CVE-2021-31207

Redhat

No data.

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