CVE-2021-26894

Windows DNS Server Remote Code Execution Vulnerability

CVSS v3 9.8 CRITICAL
CVSS v2.0 10.0 HIGH

9.8^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 3.9 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

10.0^/10

CVSS v2.0 : HIGH

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

Exploitability : 10.0 / Impact : 10.0

Access Vector NETWORK

Access Complexity LOW

Authentication NONE

Confidentiality Impact COMPLETE

Integrity Impact COMPLETE

Availability Impact COMPLETE

References

Link	Resource
https://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-26894
https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-26894	Patch Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:o:microsoft:windows_server_2008:r2:sp1:::::x64:*
	cpe:2.3:o:microsoft:windows_server_2008:sp2:::::::*
	cpe:2.3:o:microsoft:windows_server_2008:sp2:::::x86::
	cpe:2.3:o:microsoft:windows_server_2012:-:::::::*
	cpe:2.3:o:microsoft:windows_server_2012:r2::::-::-:*
	cpe:2.3:o:microsoft:windows_server_2016:-:::::::*
	cpe:2.3:o:microsoft:windows_server_2016:20h2:::::::*
	cpe:2.3:o:microsoft:windows_server_2016:1909:::::::*
	cpe:2.3:o:microsoft:windows_server_2016:2004:::::::*
	cpe:2.3:o:microsoft:windows_server_2019:-:::::::*

History

No history.

Information

Published : 2021-03-11 16:15

Updated : 2026-08-19 17:17

NVD link : CVE-2021-26894

Mitre link : CVE-2021-26894

CVE.ORG link : CVE-2021-26894

JSON object : View

Products Affected

microsoft

windows_server_2019
windows_server_2008
windows_server_2016
windows_server_2012

CWE

NVD-CWE-noinfo

{"id": "CVE-2021-26894", "cveTags": [], "metrics": {"cvssMetricV2": [{"type": "Primary", "source": "nvd@nist.gov", "cvssData": {"version": "2.0", "baseScore": 10.0, "accessVector": "NETWORK", "vectorString": "AV:N/AC:L/Au:N/C:C/I:C/A:C", "authentication": "NONE", "integrityImpact": "COMPLETE", "accessComplexity": "LOW", "availabilityImpact": "COMPLETE", "confidentialityImpact": "COMPLETE"}, "acInsufInfo": false, "impactScore": 10.0, "baseSeverity": "HIGH", "obtainAllPrivilege": false, "exploitabilityScore": 10.0, "obtainUserPrivilege": false, "obtainOtherPrivilege": false, "userInteractionRequired": false}], "cvssMetricV31": [{"type": "Secondary", "source": "secure@microsoft.com", "cvssData": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 9.8, "attackVector": "NETWORK", "baseSeverity": "CRITICAL", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H", "integrityImpact": "HIGH", "userInteraction": "NONE", "attackComplexity": "LOW", "availabilityImpact": "HIGH", "privilegesRequired": "NONE", "confidentialityImpact": "HIGH"}, "impactScore": 5.9, "exploitabilityScore": 3.9}, {"type": "Secondary", "source": "nvd@nist.gov", "cvssData": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 9.8, "attackVector": "NETWORK", "baseSeverity": "CRITICAL", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H", "integrityImpact": "HIGH", "userInteraction": "NONE", "attackComplexity": "LOW", "availabilityImpact": "HIGH", "privilegesRequired": "NONE", "confidentialityImpact": "HIGH"}, "impactScore": 5.9, "exploitabilityScore": 3.9}]}, "affected": [{"source": "secure@microsoft.com", "affectedData": [{"vendor": "Microsoft", "product": "Windows Server 2008 R2 Service Pack 1", "versions": [{"status": "affected", "version": "6.1.7601.0", "lessThan": "6.1.7601.24566", "versionType": "custom"}], "platforms": ["x64-based Systems"]}, {"vendor": "Microsoft", "product": "Windows Server 2008 R2 Service Pack 1 (Server Core installation)", "versions": [{"status": "affected", "version": "6.1.7601.0", "lessThan": "6.1.7601.24566", "versionType": "custom"}], "platforms": ["x64-based Systems"]}, {"vendor": "Microsoft", "product": "Windows Server 2008 Service Pack 2", "versions": [{"status": "affected", "version": "6.0.6003.0", "lessThan": "6.0.6003.21070", "versionType": "custom"}], "platforms": ["32-bit Systems", "x64-based Systems"]}, {"vendor": "Microsoft", "product": "Windows Server 2008 Service Pack 2 (Server Core installation)", "versions": [{"status": "affected", "version": "6.0.6003.0", "lessThan": "6.0.6003.21070", "versionType": "custom"}], "platforms": ["32-bit Systems", "x64-based Systems"]}, {"vendor": "Microsoft", "product": "Windows Server 2012", "versions": [{"status": "affected", "version": "6.2.9200.0", "lessThan": "6.2.9200.23298", "versionType": "custom"}], "platforms": ["x64-based Systems"]}, {"vendor": "Microsoft", "product": "Windows Server 2012 (Server Core installation)", "versions": [{"status": "affected", "version": "6.2.9200.0", "lessThan": "6.2.9200.23298", "versionType": "custom"}], "platforms": ["x64-based Systems"]}, {"vendor": "Microsoft", "product": "Windows Server 2012 R2", "versions": [{"status": "affected", "version": "6.3.9600.0", "lessThan": "6.3.9600.19968", "versionType": "custom"}], "platforms": ["x64-based Systems"]}, {"vendor": "Microsoft", "product": "Windows Server 2012 R2 (Server Core installation)", "versions": [{"status": "affected", "version": "6.3.9600.0", "lessThan": "6.3.9600.19968", "versionType": "custom"}], "platforms": ["x64-based Systems"]}, {"vendor": "Microsoft", "product": "Windows Server 2016", "versions": [{"status": "affected", "version": "10.0.14393.0", "lessThan": "10.0.14393.4283", "versionType": "custom"}], "platforms": ["x64-based Systems"]}, {"vendor": "Microsoft", "product": "Windows Server 2016 (Server Core installation)", "versions": [{"status": "affected", "version": "10.0.14393.0", "lessThan": "10.0.14393.4283", "versionType": "custom"}], "platforms": ["x64-based Systems"]}, {"vendor": "Microsoft", "product": "Windows Server 2019", "versions": [{"status": "affected", "version": "10.0.17763.0", "lessThan": "10.0.17763.1817", "versionType": "custom"}], "platforms": ["x64-based Systems"]}, {"vendor": "Microsoft", "product": "Windows Server 2019 (Server Core installation)", "versions": [{"status": "affected", "version": "10.0.17763.0", "lessThan": "10.0.17763.1817", "versionType": "custom"}], "platforms": ["x64-based Systems"]}, {"vendor": "Microsoft", "product": "Windows Server version 2004", "versions": [{"status": "affected", "version": "10.0.0", "lessThan": "10.0.19043.867", "versionType": "custom"}], "platforms": ["x64-based Systems"]}, {"vendor": "Microsoft", "product": "Windows Server version 20H2", "versions": [{"status": "affected", "version": "10.0.0", "lessThan": "10.0.19043.867", "versionType": "custom"}], "platforms": ["x64-based Systems"]}, {"vendor": "Microsoft", "product": "Windows Server, version 1909 (Server Core installation)", "versions": [{"status": "affected", "version": "10.0.0", "lessThan": "10.0.18363.1440", "versionType": "custom"}], "platforms": ["x64-based Systems"]}]}], "published": "2021-03-11T16:15:16.190", "references": [{"url": "https://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-26894", "source": "secure@microsoft.com"}, {"url": "https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-26894", "tags": ["Patch", "Vendor Advisory"], "source": "af854a3a-2127-422b-91ae-364da2661108"}], "vulnStatus": "Modified", "weaknesses": [{"type": "Primary", "source": "nvd@nist.gov", "description": [{"lang": "en", "value": "NVD-CWE-noinfo"}]}], "descriptions": [{"lang": "en", "value": "Windows DNS Server Remote Code Execution Vulnerability"}, {"lang": "es", "value": "Una Vulnerabilidad de Ejecuci\u00f3n de C\u00f3digo Remota del DNS Server de Windows. Este ID de CVE es diferente de CVE-2021-26877, CVE-2021-26893, CVE-2021-26895, CVE-2021-26897"}], "lastModified": "2026-08-19T17:17:45.810", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:o:microsoft:windows_server_2008:r2:sp1:*:*:*:*:x64:*", "vulnerable": true, "matchCriteriaId": "AF07A81D-12E5-4B1D-BFF9-C8D08C32FF4F"}, {"criteria": "cpe:2.3:o:microsoft:windows_server_2008:sp2:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "66CAFDB7-9D41-4E67-AB83-5EB104551FF5"}, {"criteria": "cpe:2.3:o:microsoft:windows_server_2008:sp2:*:*:*:*:x86:*:*", "vulnerable": true, "matchCriteriaId": "DC633D8A-2E7A-4115-95AC-555C42F4942D"}, {"criteria": "cpe:2.3:o:microsoft:windows_server_2012:-:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "A7DF96F8-BA6A-4780-9CA3-F719B3F81074"}, {"criteria": "cpe:2.3:o:microsoft:windows_server_2012:r2:*:*:*:-:*:-:*", "vulnerable": true, "matchCriteriaId": "44A1A867-3DAC-4C42-A091-E07B6672EE6F"}, {"criteria": "cpe:2.3:o:microsoft:windows_server_2016:-:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "041FF8BA-0B12-4A1F-B4BF-9C4F33B7C1E7"}, {"criteria": "cpe:2.3:o:microsoft:windows_server_2016:20h2:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "4A190388-AA82-4504-9D5A-624F23268C9F"}, {"criteria": "cpe:2.3:o:microsoft:windows_server_2016:1909:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "C253A63F-03AB-41CB-A03A-B2674DEA98AA"}, {"criteria": "cpe:2.3:o:microsoft:windows_server_2016:2004:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "0B60D940-80C7-49F0-8F4E-3F99AC15FA82"}, {"criteria": "cpe:2.3:o:microsoft:windows_server_2019:-:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "DB79EE26-FC32-417D-A49C-A1A63165A968"}], "operator": "OR"}]}], "sourceIdentifier": "secure@microsoft.com"}