Win32k Information Disclosure Vulnerability

MonitorCVSS 5.5CVE-2026-62743Aug 11, 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

Win32K (Windows kernel graphics driver) contains an out-of-bounds read vulnerability that allows a local authenticated attacker to disclose sensitive kernel memory. The attacker must have valid user-level access to the system and execute code locally to trigger the vulnerability.

What this means
What could happen
A local attacker with user-level access could read sensitive kernel memory from the Win32K graphics driver, potentially exposing system information or credentials.
Who's at risk
Windows server and workstation administrators responsible for Windows 10, Windows 11, Windows Server 2016, 2019, 2022, and 2025 systems. This affects both standard installations and Server Core deployments across 32-bit, x64, and ARM64 architectures.
How it could be exploited
An attacker with a local user account could execute code that triggers an out-of-bounds read in Win32K, allowing them to access memory regions they should not be able to read. This requires running malicious code on the machine itself, not remotely.
Prerequisites
  • Valid local user account on the affected Windows system
  • Ability to execute code with user-level privileges
Requires local user accessLow complexity attackAffects all Windows OS versions from 2016 onwardDisclosure of sensitive kernel memory
Exploitability
Unlikely to be exploited — EPSS score 0.4%
Affected products (26)
26 with fix
ProductAffected VersionsFix Status
Windows 10 Version 1809 for 32-bit SystemsAll versionsBuild 10.0.17763.9115
Windows 10 Version 1809 for x64-based SystemsAll versionsBuild 10.0.17763.9115
Windows Server 2019All versionsBuild 10.0.17763.9115
Windows Server 2019 (Server Core installation)All versionsBuild 10.0.17763.9115
Windows Server 2022All versionsBuild 10.0.20348.5499
Remediation & Mitigation
0/3
Schedule — requires maintenance window
0/2

Patching may require device reboot — plan for process interruption

Windows Server 2016
HOTFIXApply August 2026 Windows security update to your Windows Server 2016, 2019, 2022, and 2025 systems
All products
HOTFIXApply August 2026 Windows security update to your Windows 10 and Windows 11 systems
Long-term hardening
0/1
HARDENINGRestrict local system access to authorized personnel only through physical security and access controls
API: /api/v1/advisories/845dfdb6-45f4-4fa8-bfb2-a8854f7435c0

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