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CVE-2026-83902 Microsoft CVE debrief

A heap-based buffer overflow in Windows Direct Composition allows an authorized attacker to elevate privileges locally. Multiple Windows versions are affected, including Windows 10, Windows 11, and Windows Server. Microsoft has released patches for these vulnerabilities. The vulnerability is a high-severity elevation of privilege vulnerability in Windows Direct Composition. Defenders should prioritize patching affected Windows versions and verify system inventory to mitigate potential local privilege elevation attempts. Affected versions include Windows 10 Version 1809, Windows 10 Version 21H2, Windows 10 Version 22H2, Windows 11 version 23H2, Windows 11 Version 23H2, Windows 11 24

Vendor
Microsoft
Product
Windows 10 Version 1809
CVSS
HIGH 7.8
CISA KEV
Not listed in stored evidence
Original CVE published
2026-10-13
Original CVE updated
2026-10-13
Advisory published
2026-10-13
Advisory updated
2026-10-13

Who should care

Defenders for Windows systems, particularly those responsible for patch management and vulnerability assessment. This includes security teams, IT administrators, and operators who manage Windows deployments. They should prioritize patching affected Windows versions and verify system inventory to mitigate potential local privilege elevation attempts.

Why it matters

CVE-2026-83902 is a high-severity elevation of privilege vulnerability in Windows Direct Composition. Defenders should prioritize patching affected Windows versions and verify system inventory to mitigate potential local privilege elevation attempts.

  • Local privilege elevation requires verification
  • Patching is required for affected Windows versions
  • Inventory and verification of affected systems are necessary

Technical summary

The vulnerability is a heap-based buffer overflow in Windows Direct Composition, allowing an authorized attacker to elevate privileges locally. Affected versions include Windows 10 Version 1809, Windows 10 Version 21H2, Windows 10 Version 22H2, Windows 11 version 23H2, Windows 11 Version 23H2, Windows 11 Version 24H2, Windows 11 Version 25H2, Windows 11 version 26H1, Windows 11 Version 26H2, Windows Server 2019, Windows Server 2022, and Windows Server 2025.

Defensive priority

Apply patches immediately for Windows Direct Composition Elevation of Privilege Vulnerability

Recommended defensive actions

  • Apply patches for Windows 10 Version 1809, Windows 10 Version 21H2, Windows 10 Version 22H2, Windows 11 version 23H2, Windows 11 Version 23H2, Windows 11 Version 24H2, Windows 11 Version 25H2, Windows 11 version 26H1, 11
  • Inventory and verify affected Windows versions
  • Monitor for local privilege elevation attempts

Evidence notes

The CVE record and NVD entry provide details on the vulnerability. Microsoft has released a patch for this vulnerability. The vulnerability is a heap-based buffer overflow in Windows Direct Composition, allowing an authorized attacker to elevate privileges locally. The CVE record was published on 2026-10-13T18:59:55.515Z and has not been modified since then. The official CVE Program record and NVD detail page provide additional information on the vulnerability. The source item details

Sources and references

Verified primary and authoritative sources

  • CVE-2026-83902 CVE Program record

    Publisher, destination, and source semantics verified

    URL: https://www.cve.org/CVERecord?id=CVE-2026-83902

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

  • CVE-2026-83902 NVD vulnerability detail

    Publisher, destination, and source semantics verified

    URL: https://nvd.nist.gov/vuln/detail/CVE-2026-83902

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

Supplemental references

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.