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CVE-2026-69266 Microsoft CVE debrief

The CVE-2026-69266 vulnerability is a high-severity issue in Windows DHCP Server that allows remote code execution. This vulnerability affects multiple Windows versions and server installations. Defenders managing Windows DHCP Server installations, particularly those with high-risk deployments, should assess exposure and prioritize patching. The CVE record was published on 2026-09-08T17:14:53.058Z and has not been modified since then. The vulnerability is caused by an integer overflow or wraparound in Windows DHCP Server, which allows an unauthorized attacker to execute code over a network.

Vendor
Microsoft
Product
Windows 10 Version 1607
CVSS
HIGH 8.8
CISA KEV
Not listed in stored evidence
Original CVE published
2026-09-08
Original CVE updated
2026-10-08
Advisory published
2026-09-08
Advisory updated
2026-10-08

Who should care

Defenders managing Windows DHCP Server installations, particularly those with high-risk deployments, should assess exposure and prioritize patching.

Why it matters

CVE-2026-69266 is a high-severity vulnerability in Windows DHCP Server that allows remote code execution. Defenders should prioritize verifying exposure, applying patches, and monitoring for suspicious activity.

  • Verify exposure of Windows DHCP Server installations
  • Apply patches to prevent remote code execution
  • Monitor for suspicious network activity
  • Review incident response plans for potential DHCP Server exploitation

Technical summary

Integer overflow or wraparound in Windows DHCP Server allows an unauthorized attacker to execute code over a network, affecting multiple Windows versions and server installations. The vulnerability is a high-severity issue, with a CVSS score of 8.8 and a severity rating of HIGH. The CVE record and source item provide details on the vulnerability, but limited information is available on exploitation or victim impact.

Defensive priority

Defenders should prioritize verifying exposure of Windows DHCP Server installations and applying vendor patches, focusing on high-risk deployments.

Recommended defensive actions

  • Verify Windows DHCP Server installations for exposure
  • Apply vendor patches for affected versions
  • Monitor for suspicious network activity
  • Review and update incident response plans

Evidence notes

The CVE record and source item provide details on the vulnerability, but limited information is available on exploitation or victim impact. The official CVE Program record (cve-org) and the NIST NVD detail page (nvd) offer source-provided CVE metadata and vulnerability assessments. The source item (source-item) provides additional details on the vulnerability. However, there is no information on known or confirmed exploitation. Defenders should verify exposure of Windows DHCP Server

Sources and references

Verified primary and authoritative sources

  • CVE-2026-69266 CVE Program record

    Publisher, destination, and source semantics verified

    URL: https://www.cve.org/CVERecord?id=CVE-2026-69266

    CVE Program - Official CVE Program record with source-provided CVE metadata.

  • CVE-2026-69266 NVD vulnerability detail

    Publisher, destination, and source semantics verified

    URL: https://nvd.nist.gov/vuln/detail/CVE-2026-69266

    NIST National Vulnerability Database - Official NIST NVD detail page and source-specific vulnerability assessment.

Supplemental references

  • Windows DHCP Server Remote Code Execution Vulnerability

    Unverified legacy reference

    URL: https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2026/69xxx/CVE-2026-69266.json

    cve_program_cvelist_v5

  • Source reference

    Unverified legacy reference

    URL: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-69266

    Supplemental source - vendor-advisory, patch

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.