CVE-2026-83787: Microsoft Windows DHCP Server authentication bypass

CVE-2026-83787 · Severity: medium · CVSS 5.5 · Published 2026-10-13

Windows DHCP Server, which manages IP address assignment on networks, has a flaw that allows an authorized user to bypass a security feature through insufficient verification of data authenticity. An attacker with local access could exploit this to circumvent intended security controls and potentially gain unauthorized capabilities on the network infrastructure.

Technologies: Microsoft Windows DHCP Server, Microsoft Windows 10 1607, Microsoft Windows 10 1809, Microsoft Windows Server 2012, Microsoft Windows Server 2016, Microsoft Windows Server 2019, Microsoft Windows Server 2022, Microsoft Windows Server 2025. Vendors: Microsoft.

Quick answers

Is CVE-2026-83787 exploited in the wild?
No. Junglewise Threat Intelligence has no report of CVE-2026-83787 being exploited in the wild.
How severe is CVE-2026-83787?
Medium severity, with a CVSS score of 5.5, published 13 October 2026.
Which products and versions are affected?
Microsoft Windows DHCP Server.
Is there a fix for CVE-2026-83787?
No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
How is CVE-2026-83787 attacked?
It is attacked with local access, in an operating system.
Am I affected by CVE-2026-83787?
Check whether you run Microsoft Windows DHCP Server, Microsoft Windows 10 1607, Microsoft Windows 10 1809 or one of the others listed. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

Technical details

The vulnerability exists in Windows DHCP Server due to insufficient verification of data authenticity, allowing an authorized attacker with local access to bypass a security feature. This is a privilege escalation or security control bypass rather than a remote code execution issue. A fix is available from Microsoft.

Affected products

  • Microsoft Windows DHCP Server

Timeline

  • 2026-10-13: disclosed

References

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