OTPulse

Windows DHCP Server Information Disclosure Vulnerability

MonitorCVSS 6.5CVE-2026-62718Aug 11, 2026
Microsoft
IT in OT - Windows Server and Active Directory are widely deployed in OT environments
Attack path
Attack VectorAdjacent
Auth RequiredNone
ComplexityLow
User InteractionNone needed
Summary

Integer underflow vulnerability in Windows DHCP Server allows an unauthorized attacker on an adjacent network to disclose information from server memory. An attacker can send a malformed DHCP packet to trigger the underflow condition, causing the DHCP Server to leak sensitive data in responses. Affects Windows Server 2016, 2019, 2022, 2025 and Windows 10 systems with DHCP Server role enabled.

What this means
What could happen
An attacker on an adjacent network (same subnet) could trigger an integer underflow in Windows DHCP Server to extract sensitive information from memory, such as configuration details, credentials, or other system data.
Who's at risk
Organizations running Windows Server 2016, 2019, 2022, or 2025 with DHCP Server role enabled, and Windows 10 systems acting as DHCP servers. This affects network infrastructure administrators and IT teams responsible for DHCP services in corporate and municipal networks.
How it could be exploited
An attacker sends a specially crafted DHCP request on the local network segment. The Windows DHCP Server processes the malformed packet, triggering an integer underflow that leaks uninitialized or sensitive memory back to the attacker in the DHCP response.
Prerequisites
  • Attacker must be on the same network segment (adjacent network) as the DHCP server
  • DHCP Server role must be enabled on the target Windows Server or Windows system
Remotely exploitable from adjacent networkNo authentication requiredLow complexity attackInformation disclosure (potential exposure of sensitive memory data)
Exploitability
Unlikely to be exploited — EPSS score 0.5%
Affected products (12)
12 with fix
ProductAffected VersionsFix Status
Windows 10 Version 1809 for 32-bit SystemsAll versionsBuild 10.0.17763.9115
Windows 10 Version 1809 for x64-based SystemsAll versionsBuild 10.0.17763.9115
Windows Server 2019All versionsBuild 10.0.17763.9115
Windows Server 2019 (Server Core installation)All versionsBuild 10.0.17763.9115
Windows Server 2022All versionsBuild 10.0.20348.5499
Windows Server 2022 (Server Core installation)All versionsBuild 10.0.20348.5499
Windows Server 2025 (Server Core installation)All versionsBuild 10.0.26100.33296
Windows Server 2025All versionsBuild 10.0.26100.33296
Remediation & Mitigation
0/8
Do now
0/1
WORKAROUNDDisable DHCP Server role on systems where it is not required
Schedule — requires maintenance window
0/6

Patching may require device reboot — plan for process interruption

Windows Server 2019
HOTFIXUpdate Windows Server 2019 to Build 10.0.17763.9115 or later
Windows Server 2022
HOTFIXUpdate Windows Server 2022 to Build 10.0.20348.5499 or later
Windows Server 2025
HOTFIXUpdate Windows Server 2025 to Build 10.0.26100.33296 or later
Windows Server 2016
HOTFIXUpdate Windows Server 2016 to Build 10.0.14393.9418 or later
All products
HOTFIXUpdate Windows 10 Version 1809 to Build 10.0.17763.9115 or later
HOTFIXUpdate Windows 10 Version 1607 to Build 10.0.14393.9418 or later
Long-term hardening
0/1
HARDENINGRestrict DHCP server access to trusted network segments using network segmentation or VLAN isolation
View full vendor advisory
API: /api/v1/advisories/741987e1-5b39-48d9-82a7-20eaac1638dc

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Windows DHCP Server Information Disclosure Vulnerability | CVSS 6.5 - OTPulse