CVE-2021-34523 - Vulnerability Details - OpenCVE

Microsoft Exchange Server Elevation of Privilege Vulnerability

No CVSS v4.0

Attack Vector Local

Attack Complexity Low

Privileges Required None

Scope Changed

Confidentiality Impact High

Integrity Impact High

Availability Impact None

User Interaction None

No CVSS v3.0

Access Vector Network

Access Complexity Low

Authentication None

Confidentiality Impact Partial

Integrity Impact Partial

Availability Impact Partial

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-2021-34523
https://www.zerodayinitiative.com/advisories/ZDI-21-822/

History

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

Type	Values Removed	Values Added
Metrics	epss `{'score': 0.94149}`	epss `{'score': 0.94053}`

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

Type	Values Removed	Values Added
Metrics	epss `{'score': 0.93973}`	epss `{'score': 0.94149}`

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: 2021-07-14T17:54:38.000Z

Updated: 2025-07-30T01:38:06.414Z

Reserved: 2021-06-09T00:00:00.000Z

Link: CVE-2021-34523

Vulnrichment

Updated: 2024-08-04T00:12:50.370Z

NVD

Status : Modified

Published: 2021-07-14T18:15:12.347

Modified: 2024-11-21T06:10:35.977

Link: CVE-2021-34523

Redhat

No data.

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