CVE-2026-45602: Windows Dynamic Host Configuration Protocol (DHCP) Tampering Vulnerability

Synopsis

An unauthenticated network tampering vulnerability affects the Windows DHCP Server component across multiple Windows 10 and Windows 11 versions. The flaw is reachable over the network without any credentials, and no victim interaction is required to trigger it. Successful exploitation allows an attacker to tamper with DHCP server data, enabling manipulation of network configuration delivered to clients. Patched-image rebuilds at the fix versions are available on HarborGuard for environments running affected Windows versions.

HarborGuard Coverage

Exploit Conditions

• Network reachabilityRequired

  The attacker must reach the DHCP Server service over the network; the vulnerability is exposed to any host with network access to the server.

• AuthenticationNot required

  No credentials or account of any privilege level are needed to exploit this vulnerability.

• Victim interactionNot required

  Exploitation is fully remote and unsolicited; no user action or social engineering is required.

• Attack complexityDetail

  The exploit is reliable and condition-free, requiring no race conditions, memory-layout knowledge, or other environmental factors.

Blast Radius

• An attacker can modify DHCP lease responses, redirecting network clients to attacker-controlled gateways or DNS servers.
• Manipulated DHCP responses allow traffic interception or redirection for any client that receives a poisoned lease.
• Confidentiality of data in transit for affected clients is compromised because routing can be silently altered without client awareness.