Stack-based buffer overflow in Microsoft products - CVE-2026-78439

Vulnerability details

The vulnerability allows a remote attacker to execute arbitrary code on the target system.

The vulnerability exists due to a boundary error in Microsoft Office Graphics Component. A remote unauthenticated attacker can trick a victim to open a specially crafted file, trigger stack-based buffer overflow and execute arbitrary code on the target system.

Successful exploitation of this vulnerability may result in complete compromise of vulnerable system.

Affected software

How to mitigate CVE-2026-78439

External References

• https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-78439

Related Security Bulletins

• Remote code execution in Microsoft Office Graphics Component