Heap-based buffer overflow in Microsoft Windows and Windows Server - CVE-2026-118277

Vulnerability details

The vulnerability allows a local user to escalate privileges beyond their own AppContainer and perform actions within the isolated graphics compilation service's security context.

The vulnerability exists due to a heap-based buffer overflow in Windows Advanced Rasterization Platform when processing graphics data submitted to the isolated graphics compilation service. A local user can run a malicious application locally inside an AppContainer and submit specially crafted graphics data to perform unauthorized actions within the service's isolated security context.

Affected software

How to mitigate CVE-2026-118277

External References

• https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2026-118277
• https://support.microsoft.com/help/5126651

Related Security Bulletins

• Multiple vulnerabilities in Microsoft Windows