CVE-2026-50387 Windows GDI Elevation of Privilege Vulnerability
A stack-based buffer overflow in Windows GDI allows local attackers to elevate privileges.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-50387?
CVE-2026-50387 is a high-severity memory corruption vulnerability in Microsoft 365 Copilot, published on 14 Jul 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
Stack-based buffer overflow in Windows GDI allows an authorized attacker to elevate privileges locally.
Weakness: CWE-121
Which versions are affected by CVE-2026-50387?
It affects 16 products.
Products include Microsoft 365 Copilot, Microsoft Microsoft 365, Microsoft Office 2021, Microsoft Office 2024, Microsoft Windows 10 1607, Microsoft Windows 10 1809 and 10 more.
How do I fix CVE-2026-50387?
No fix has been published for CVE-2026-50387 yet. Limit exposure of the affected software until one is available.
Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.
Is CVE-2026-50387 being exploited?
There is no known exploitation of CVE-2026-50387 in the wild and no public exploit code.
Other vulnerabilities in Microsoft 365 Copilot
- CVE-2026-85885 Microsoft 365 Copilot Elevation of Privilege Vulnerability
- CVE-2026-50517 Microsoft M365 Copilot Remote Code Execution Vulnerability
- CVE-2026-54130 M365 Copilot Information Disclosure Vulnerability
- CVE-2025-60724 GDI+ Remote Code Execution Vulnerability
- CVE-2025-53766 GDI+ Remote Code Execution Vulnerability
Sources
Also known as GHSA-9q2r-53gw-xr3v.