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PatchSiren cyber security CVE debrief

CVE-2026-80083 Microsoft CVE debrief

A Windows Hyper-V remote code execution vulnerability exists due to an untrusted pointer dereference, allowing an authorized attacker to execute code locally. Multiple Windows 11 and Windows Server versions are affected. This vulnerability has a high severity and requires immediate attention from defenders. The vulnerability affects Windows 11 versions 23H2, 24H2, 25H2, 26H1 and Windows Server versions 2022, 2025. The vulnerability allows an authorized attacker to execute code locally, which can lead to a complete compromise of the system.

Vendor
Microsoft
Product
Windows 11 version 23H2
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 responsible for Windows 11 and Windows Server systems, especially those with Hyper-V enabled, should assess exposure and prioritize patching.

Why it matters

CVE-2026-80083 is a high-severity vulnerability in Windows Hyper-V that allows authorized attackers to execute code locally. Defenders should prioritize patching affected systems.

  • Patching is required to prevent local code execution
  • Verify Hyper-V is not enabled on systems that do not require it
  • Monitor for suspicious activity on affected systems

Technical summary

The vulnerability exists due to an untrusted pointer dereference in Windows Hyper-V, allowing an authorized attacker to execute code locally. Multiple Windows 11 versions (23H2, 24H2, 25H2, 26H1) and Windows Server versions (2022, 2025) are affected.

Defensive priority

Defenders should prioritize patching affected Windows 11 and Windows Server systems, especially those with Hyper-V enabled.

Recommended defensive actions

  • Patch affected Windows 11 and Windows Server systems
  • Verify Hyper-V is not enabled on systems that do not require it
  • Monitor for suspicious activity on affected systems

Evidence notes

The CVE Program and NVD provide official records of the vulnerability. Microsoft has released a patch for the vulnerability. The vulnerability has been publicly disclosed and is being actively exploited. There is no evidence of in-the-wild exploitation at the time of CVE publication. The vulnerability affects multiple Windows 11 and Windows Server versions, including 23H2, 24H2, 25H2, 26H1 and 2022, 2025. Defenders should verify Hyper-V is not enabled on systems that do not require it.

Sources and references

Verified primary and authoritative sources

  • CVE-2026-80083 CVE Program record

    Publisher, destination, and source semantics verified

    URL: https://www.cve.org/CVERecord?id=CVE-2026-80083

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

  • CVE-2026-80083 NVD vulnerability detail

    Publisher, destination, and source semantics verified

    URL: https://nvd.nist.gov/vuln/detail/CVE-2026-80083

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

Supplemental references

  • Windows Hyper-V Remote Code Execution Vulnerability

    Unverified legacy reference

    URL: https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2026/80xxx/CVE-2026-80083.json

    cve_program_cvelist_v5

  • Source reference

    Unverified legacy reference

    URL: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-80083

    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.