CVE-2026-77502: Windows DHCP Server Denial of Service Vulnerability

Published Sep 8, 2026
·
Updated

Out-of-bounds read in Windows DHCP Server allows an unauthorized attacker to deny service over a network.

Other sources

Windows DHCP Server Denial of Service Vulnerability

Microsoft

Affected Software

17 affected componentsFixes available
Microsoft Windows DHCP Server
Microsoft Windows Server 2012<6.2.9200.26349
6.2.9200.26349
Microsoft Windows Server 2022<10.0.20348.5622
10.0.20348.5622
Microsoft Windows Server 2019<10.0.17763.9245
10.0.17763.9245
Microsoft Windows Server 2012<6.2.9200.26349
6.2.9200.26349
Microsoft Windows Server 2016<10.0.14393.9512
10.0.14393.9512
Microsoft Windows Server 2019<10.0.17763.9245
10.0.17763.9245
Microsoft Windows Server 2025<10.0.26100.33438
10.0.26100.33438
Microsoft Windows Server 2012 R2<6.3.9600.23397
6.3.9600.23397
Microsoft Windows Server 2016<10.0.14393.9512
10.0.14393.9512
Microsoft Windows 10=1607
10.0.14393.9512
Microsoft Windows Server 2012 R2<6.3.9600.23397
6.3.9600.23397
Microsoft Windows Server 2025<10.0.26100.33438
10.0.26100.33438
Microsoft Windows 10=1607
10.0.14393.9512
Microsoft Windows 10=1809
10.0.17763.9245
Microsoft Windows 10=1809
10.0.17763.9245
Microsoft Windows Server 2022<10.0.20348.5622
10.0.20348.5622

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 6.2.9200.26349Patch KB5123065
  2. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 10.0.20348.5622Patch KB5122882
  3. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 10.0.17763.9245Patch KB5122876
  4. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 10.0.14393.9512Patch KB5123099
  5. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 6.3.9600.23397Patch KB5123066
  6. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 10.0.26100.33438Patch KB5122871

Event History

Sep 8, 2026
CVE Published
via Microsoft·02:00 PM
Data Sourced
via Microsoft·02:00 PM
DescriptionSeverityWeaknessAffected Software
Updated
via Microsoft·02:00 PM
Affected Software
Updated
via Microsoft·02:00 PM
Description
CVE Published
via MITRE·05:13 PM
Data Sourced
via MITRE·05:13 PM
DescriptionSeverity
Data Sourced
via NVD·06:20 PM
DescriptionSeverityWeakness

Frequently Asked Questions

1

Who can exploit this vulnerability?

An unauthorized attacker can exploit it over the network. No privileges or user interaction are required.

2

What is the likely impact of successful exploitation?

Successful exploitation can deny service on the affected Windows DHCP Server. The provided severity vector indicates availability impact only, with no stated confidentiality or integrity impact.

3

Which systems should be assessed?

Assess systems running Microsoft Windows DHCP Server, including the listed Windows 10, Windows Server 2012, 2012 R2, 2016, 2019, 2022, and 2025 products.

Contact

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