Windows Win32k Elevation of Privilege Vulnerability

Plan PatchCVSS 7.8CVE-2026-54986Jul 14, 2026
Microsoft
IT in OT - Windows Server and Active Directory are widely deployed in OT environments
Attack path
Attack VectorLocal
Auth RequiredLow
ComplexityLow
User InteractionNone needed
Summary

A heap-based buffer overflow exists in the Windows Win32K graphics kernel subsystem. An authorized user with local logon access could provide specially crafted input that triggers the overflow, allowing them to execute code with elevated system privileges and bypass normal access controls.

What this means
What could happen
A logged-in user on an affected Windows system could exploit a heap buffer overflow in the graphics subsystem to gain elevated privileges, allowing them to install software, modify settings, or access sensitive data that requires admin rights.
Who's at risk
Windows servers and workstations running versions 10.0.14393 through 10.0.28000, including Windows Server 2016, 2019, 2022, 2025, and Windows 10/11 systems. Affects both 32-bit, 64-bit, and ARM64 architectures. Any organization using affected Windows systems needs to apply patches.
How it could be exploited
An attacker with a user account on the target Windows system could craft a malicious input to the Win32K graphics kernel that triggers a heap buffer overflow. By doing so, they could execute arbitrary code with higher privileges, bypassing normal access controls.
Prerequisites
  • Valid user account on the affected Windows system
  • Local access to the machine (interactive logon or remote desktop)
  • No additional software or special configuration required
Low complexity attackAffects multiple Windows versions across 9+ yearsLocally exploitable with user-level credentials
Exploitability
Unlikely to be exploited — EPSS score 0.3%
Affected products (23)
23 with fix
ProductAffected VersionsFix Status
Windows 10 Version 1809 for 32-bit SystemsAll versionsBuild 10.0.17763.9020
Windows 10 Version 1809 for x64-based SystemsAll versionsBuild 10.0.17763.9020
Windows Server 2019All versionsBuild 10.0.17763.9020
Windows Server 2019 (Server Core installation)All versionsBuild 10.0.17763.9020
Windows Server 2022All versionsBuild 10.0.20348.5386
Remediation & Mitigation
0/4
Do now
0/1
HOTFIXInstall the July 2026 Windows security update for your Windows version
Long-term hardening
0/3
HARDENINGRestrict local interactive logon to trusted personnel only
HARDENINGDisable unnecessary remote access protocols (RDP) if not required for operations
HARDENINGApply Windows security group policies to limit privilege escalation vectors
API: /api/v1/advisories/4717a1d0-0e21-40c2-9c05-5037b590de99

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Windows Win32k Elevation of Privilege Vulnerability | CVSS 7.8 - OTPulse