CVE-2026-50387 - Windows GDI Elevation of Privilege Vulnerability - is a stack-based buffer overflow in Windows GDI that can lead to elevation of privilege to SYSTEM. Microsoft lists CVSS v3.1 base score 7.8 (High) and temporal score 6.8; the vector is LOCAL, with LOW attack complexity, LOW privileges required, and no user interaction. Public disclosure and active exploitation are not reported, exploit code maturity is UNPROVEN, and Microsoft says exploitation is more likely. Because this is a local privilege escalation issue, enterprise risk is centered on systems where an attacker can already obtain local execution or low-privilege access.

Highlights:
- CVSS scores: Base 7.8 - Temporal 6.8
- Exploit status & code maturity: Publicly Disclosed: No; Exploited: No; Exploit Code Maturity: UNPROVEN.
- Impact: Elevation of Privilege; confidentiality, integrity, and availability impacts are HIGH.
- Exploitation likelihood: Exploitation More Likely; vector context is LOCAL, LOW attack complexity, LOW privileges required, and NO user interaction.
- Severity for enterprise: High severity on affected Windows systems, but lower exposure than remote attacks because exploitation requires local access. Risk is most relevant where untrusted users, local code execution, or shared workstations/servers are present.
- Patch status: available

Affected systems:
- Windows 10 1607
- Windows 10 1809
- Windows 10 21H2
- Windows 10 22H2
- Windows 11 24H2
- Windows 11 25H2
- Windows 11 26H1
- Windows 11 unspecified
- Windows Server 2012
- Windows Server 2012 R2
- Windows Server 2016
- Windows Server 2019
- Windows Server 2022
- Windows Server 2025