Type Confusion in Windows DHCP Server

Publication date: 2026-09-08

Last updated on: 2026-09-24

Assigner: Microsoft Corporation

Description

Access of resource using incompatible type ('type confusion') in Windows DHCP Server allows an unauthorized attacker to deny service over a network.

CVSS Scores

EPSS Scores

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Meta Information

Published

2026-09-08

Last Modified

2026-09-24

Generated

2026-09-29

AI Q&A

2026-09-09

EPSS Evaluated

2026-09-27

NVD

CVE-2026-77889

Affected Vendors & Products

Vendor	Product	Version / Range
microsoft	windows_dhcp_server	*

Helpful Resources

Exploitability

CWE

KEV

CWE ID	Description
CWE-843	The product allocates or initializes a resource such as a pointer, object, or variable using one type, but it later accesses that resource using a type that is incompatible with the original type.

Attack-Flow Graph

Executive Summary

This vulnerability is a type confusion issue in Windows DHCP Server. It allows an unauthorized attacker to cause a denial of service over a network by exploiting how the server handles different data types.

Impact Analysis

An attacker could exploit this to disrupt network services by crashing the DHCP server, leading to loss of network connectivity for devices relying on DHCP for IP address assignment.

Mitigation Strategies

Apply the latest security updates from Microsoft for Windows DHCP Server to address the type confusion vulnerability. Monitor network traffic for unusual DHCP server activity and disable the service if suspicious behavior is detected.

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