CVE-2023-21529

Microsoft Exchange Server Remote Code Execution Vulnerability

CVSS v3 8.8 HIGH

8.8^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.8 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://msrc.microsoft.com/update-guide/vulnerability/CVE-2023-21529	Patch Vendor Advisory
https://msrc.microsoft.com/update-guide/vulnerability/CVE-2023-21529	Patch Vendor Advisory
https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2023-21529	US Government Resource
https://www.microsoft.com/en-us/security/blog/2026/04/06/storm-1175-focuses-gaze-on-vulnerable-web-facing-assets-in-high-tempo-medusa-ransomware-operations/	Technical Description

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:microsoft:exchange_server:2013:cumulative_update_23::::::
	cpe:2.3:a:microsoft:exchange_server:2016:cumulative_update_23::::::
	cpe:2.3:a:microsoft:exchange_server:2019:cumulative_update_11::::::
	cpe:2.3:a:microsoft:exchange_server:2019:cumulative_update_12::::::

History

No history.

Information

Published : 2023-02-14 20:15

Updated : 2026-08-19 17:18

NVD link : CVE-2023-21529

Mitre link : CVE-2023-21529

CVE.ORG link : CVE-2023-21529

JSON object : View

Products Affected

microsoft

exchange_server

CWE

CWE-502

Deserialization of Untrusted Data

{"id": "CVE-2023-21529", "cveTags": [], "metrics": {"ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2023-21529", "role": "CISA Coordinator", "options": [{"exploitation": "active"}, {"automatable": "no"}, {"technicalImpact": "total"}], "version": "2.0.3", "timestamp": "2023-02-15T00:00:00+00:00"}}], "cvssMetricV31": [{"type": "Secondary", "source": "secure@microsoft.com", "cvssData": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 8.8, "attackVector": "NETWORK", "baseSeverity": "HIGH", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H", "integrityImpact": "HIGH", "userInteraction": "NONE", "attackComplexity": "LOW", "availabilityImpact": "HIGH", "privilegesRequired": "LOW", "confidentialityImpact": "HIGH"}, "impactScore": 5.9, "exploitabilityScore": 2.8}]}, "affected": [{"source": "secure@microsoft.com", "affectedData": [{"vendor": "Microsoft", "product": "Microsoft Exchange Server 2013 Cumulative Update 23", "versions": [{"status": "affected", "version": "15.00.0", "lessThan": "15.00.1497.047", "versionType": "custom"}], "platforms": ["x64-based Systems"]}, {"vendor": "Microsoft", "product": "Microsoft Exchange Server 2016 Cumulative Update 23", "versions": [{"status": "affected", "version": "15.01.0", "lessThan": "15.01.2507.021", "versionType": "custom"}], "platforms": ["x64-based Systems"]}, {"vendor": "Microsoft", "product": "Microsoft Exchange Server 2019 Cumulative Update 11", "versions": [{"status": "affected", "version": "15.02.0", "lessThan": "15.02.0986.041", "versionType": "custom"}], "platforms": ["x64-based Systems"]}, {"vendor": "Microsoft", "product": "Microsoft Exchange Server 2019 Cumulative Update 12", "versions": [{"status": "affected", "version": "15.02.0", "lessThan": "15.02.1118.025", "versionType": "custom"}], "platforms": ["x64-based Systems"]}]}], "published": "2023-02-14T20:15:11.743", "references": [{"url": "https://msrc.microsoft.com/update-guide/vulnerability/CVE-2023-21529", "tags": ["Patch", "Vendor Advisory"], "source": "secure@microsoft.com"}, {"url": "https://msrc.microsoft.com/update-guide/vulnerability/CVE-2023-21529", "tags": ["Patch", "Vendor Advisory"], "source": "af854a3a-2127-422b-91ae-364da2661108"}, {"url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2023-21529", "tags": ["US Government Resource"], "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0"}, {"url": "https://www.microsoft.com/en-us/security/blog/2026/04/06/storm-1175-focuses-gaze-on-vulnerable-web-facing-assets-in-high-tempo-medusa-ransomware-operations/", "tags": ["Technical Description"], "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0"}], "vulnStatus": "Analyzed", "weaknesses": [{"type": "Secondary", "source": "secure@microsoft.com", "description": [{"lang": "en", "value": "CWE-502"}]}], "descriptions": [{"lang": "en", "value": "Microsoft Exchange Server Remote Code Execution Vulnerability"}], "lastModified": "2026-08-19T17:18:05.870", "cisaActionDue": "2026-04-27", "cisaExploitAdd": "2026-04-13", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:a:microsoft:exchange_server:2013:cumulative_update_23:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "DA166F2A-D83B-4D50-AD0B-668D813E0585"}, {"criteria": "cpe:2.3:a:microsoft:exchange_server:2016:cumulative_update_23:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "FF76AEDA-E574-40ED-B64F-8FDEF8CAC802"}, {"criteria": "cpe:2.3:a:microsoft:exchange_server:2019:cumulative_update_11:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "435343A4-BF10-461A-ABF2-D511A5FBDA75"}, {"criteria": "cpe:2.3:a:microsoft:exchange_server:2019:cumulative_update_12:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "B23C8E3E-5243-4DA6-B9AA-F6053084B55E"}], "operator": "OR"}]}], "sourceIdentifier": "secure@microsoft.com", "cisaRequiredAction": "Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.", "cisaVulnerabilityName": "Microsoft Exchange Server Deserialization of Untrusted Data Vulnerability"}