CVE-2026-83665

Null pointer dereference in Windows DHCP Server allows an unauthorized attacker to deny service over a network.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-83665	Patch Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:o:microsoft:windows_10_1809:::::::x64:*
	cpe:2.3:o:microsoft:windows_10_1809:::::::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:::::::x64:*
	cpe:2.3:o:microsoft:windows_server_2019:::::::x64:*
	cpe:2.3:o:microsoft:windows_server_2022:::::::x64:*
	cpe:2.3:o:microsoft:windows_server_2025:::::::x64:*

History

29 Oct 2026, 18:25

Type	Values Removed	Values Added
First Time		Microsoft windows Server 2019 Microsoft Microsoft windows 10 1809 Microsoft windows Server 2012 Microsoft windows Server 2016 Microsoft windows Server 2025 Microsoft windows Server 2022
CPE		cpe:2.3:o:microsoft:windows_server_2019:::::::x64:* cpe:2.3:o:microsoft:windows_server_2016:::::::x64:* cpe:2.3:o:microsoft:windows_10_1809:::::::x64:* cpe:2.3:o:microsoft:windows_server_2025:::::::x64:* cpe:2.3:o:microsoft:windows_10_1809:::::::x86:* cpe:2.3:o:microsoft:windows_server_2022:::::::x64:* cpe:2.3:o:microsoft:windows_server_2012:r2:::::::* cpe:2.3:o:microsoft:windows_server_2012:-:::::::*
References	~~() https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-83665 -~~	() https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-83665 - Patch, Vendor Advisory

13 Oct 2026, 19:20

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-13 19:20

Updated : 2026-10-29 18:25

NVD link : CVE-2026-83665

Mitre link : CVE-2026-83665

CVE.ORG link : CVE-2026-83665

JSON object : View

Products Affected

microsoft

windows_server_2016
windows_server_2019
windows_server_2025
windows_10_1809
windows_server_2022
windows_server_2012

CWE

CWE-476

NULL Pointer Dereference

{"id": "CVE-2026-83665", "cveTags": [], "metrics": {"ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-83665", "role": "CISA Coordinator", "options": [{"exploitation": "none"}, {"automatable": "yes"}, {"technicalImpact": "partial"}], "version": "2.0.3", "timestamp": "2026-10-13T22:07:18.093870Z"}}], "cvssMetricV31": [{"type": "Secondary", "source": "secure@microsoft.com", "cvssData": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 7.5, "attackVector": "NETWORK", "baseSeverity": "HIGH", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H", "integrityImpact": "NONE", "userInteraction": "NONE", "attackComplexity": "LOW", "availabilityImpact": "HIGH", "privilegesRequired": "NONE", "confidentialityImpact": "NONE"}, "impactScore": 3.6, "exploitabilityScore": 3.9}]}, "affected": [{"source": "secure@microsoft.com", "affectedData": [{"vendor": "Microsoft", "product": "Windows 10 Version 1607", "versions": [{"status": "affected", "version": "10.0.14393.0", "lessThan": "10.0.14393.9612", "versionType": "custom"}], "platforms": ["32-bit Systems", "x64-based Systems"]}, {"vendor": "Microsoft", "product": "Windows 10 Version 1809", "versions": [{"status": "affected", "version": "10.0.17763.0", "lessThan": "10.0.17763.9376", "versionType": "custom"}], "platforms": ["32-bit Systems", "x64-based Systems"]}, {"vendor": "Microsoft", "product": "Windows Server 2012", "versions": [{"status": "affected", "version": "6.2.9200.0", "lessThan": "6.2.9200.26434", "versionType": "custom"}], "platforms": ["x64-based Systems"]}, {"vendor": "Microsoft", "product": "Windows Server 2012 (Server Core installation)", "versions": [{"status": "affected", "version": "6.2.9200.0", "lessThan": "6.2.9200.26434", "versionType": "custom"}], "platforms": ["x64-based Systems"]}, {"vendor": "Microsoft", "product": "Windows Server 2012 R2", "versions": [{"status": "affected", "version": "6.3.9600.0", "lessThan": "6.3.9600.23470", "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": "6.3.9600.23470", "versionType": "custom"}], "platforms": ["x64-based Systems"]}, {"vendor": "Microsoft", "product": "Windows Server 2016", "versions": [{"status": "affected", "version": "10.0.14393.0", "lessThan": "10.0.14393.9612", "versionType": "custom"}], "platforms": ["x64-based Systems"]}, {"vendor": "Microsoft", "product": "Windows Server 2016 (Server Core installation)", "versions": [{"status": "affected", "version": "10.0.14393.0", "lessThan": "10.0.14393.9612", "versionType": "custom"}], "platforms": ["x64-based Systems"]}, {"vendor": "Microsoft", "product": "Windows Server 2019", "versions": [{"status": "affected", "version": "10.0.17763.0", "lessThan": "10.0.17763.9376", "versionType": "custom"}], "platforms": ["x64-based Systems"]}, {"vendor": "Microsoft", "product": "Windows Server 2019 (Server Core installation)", "versions": [{"status": "affected", "version": "10.0.17763.0", "lessThan": "10.0.17763.9376", "versionType": "custom"}], "platforms": ["x64-based Systems"]}, {"vendor": "Microsoft", "product": "Windows Server 2022", "versions": [{"status": "affected", "version": "10.0.20348.0", "lessThan": "10.0.20348.5761", "versionType": "custom"}], "platforms": ["x64-based Systems"]}, {"vendor": "Microsoft", "product": "Windows Server 2025", "versions": [{"status": "affected", "version": "10.0.26100.0", "lessThan": "10.0.26100.33650", "versionType": "custom"}], "platforms": ["x64-based Systems"]}, {"vendor": "Microsoft", "product": "Windows Server 2025 (Server Core installation)", "versions": [{"status": "affected", "version": "10.0.26100.0", "lessThan": "10.0.26100.33650", "versionType": "custom"}], "platforms": ["x64-based Systems"]}]}], "published": "2026-10-13T19:20:08.023", "references": [{"url": "https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-83665", "tags": ["Patch", "Vendor Advisory"], "source": "secure@microsoft.com"}], "vulnStatus": "Analyzed", "weaknesses": [{"type": "Secondary", "source": "secure@microsoft.com", "description": [{"lang": "en", "value": "CWE-476"}]}], "descriptions": [{"lang": "en", "value": "Null pointer dereference in Windows DHCP Server allows an unauthorized attacker to deny service over a network."}], "lastModified": "2026-10-29T18:25:58.600", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:o:microsoft:windows_10_1809:*:*:*:*:*:*:x64:*", "vulnerable": true, "matchCriteriaId": "15BDFD52-C4C7-440A-B97C-D7637E77AFAC", "versionEndExcluding": "10.0.17763.9376"}, {"criteria": "cpe:2.3:o:microsoft:windows_10_1809:*:*:*:*:*:*:x86:*", "vulnerable": true, "matchCriteriaId": "A1A74FEC-9922-4060-A2C0-06080FB4DDA8", "versionEndExcluding": "10.0.17763.9376"}, {"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": "DB18C4CE-5917-401E-ACF7-2747084FD36E"}, {"criteria": "cpe:2.3:o:microsoft:windows_server_2016:*:*:*:*:*:*:x64:*", "vulnerable": true, "matchCriteriaId": "D2A98BDA-8301-431C-BD7D-27C318AF2397", "versionEndExcluding": "10.0.14393.9612"}, {"criteria": "cpe:2.3:o:microsoft:windows_server_2019:*:*:*:*:*:*:x64:*", "vulnerable": true, "matchCriteriaId": "D8CE3341-8771-4A25-9BF6-2A280D9C536C", "versionEndExcluding": "10.0.17763.9376"}, {"criteria": "cpe:2.3:o:microsoft:windows_server_2022:*:*:*:*:*:*:x64:*", "vulnerable": true, "matchCriteriaId": "A98E694F-9390-488A-A7FB-3E7BF7E988F8", "versionEndExcluding": "10.0.20348.5761"}, {"criteria": "cpe:2.3:o:microsoft:windows_server_2025:*:*:*:*:*:*:x64:*", "vulnerable": true, "matchCriteriaId": "D95E80FE-F34C-4805-9A66-75D090E65BBB", "versionEndExcluding": "10.0.26100.33650"}], "operator": "OR"}]}], "sourceIdentifier": "secure@microsoft.com"}