Junglewise Threat Intelligence

CVE-2026-56189: Microsoft Windows Media Foundation heap overflow code execution

CVE-2026-56189 · Severity: high · CVSS 7.8 · Published 2026-07-14

Technologies: Microsoft Windows Server 2012, Microsoft Windows 10, Microsoft Windows 11. Vendors: Microsoft.

Executive brief

A security vulnerability exists in the Windows component responsible for processing multimedia files. If a user is tricked into opening a specially crafted media file, an attacker could gain the ability to run unauthorized code on the victim's computer. This could lead to a full system compromise, data theft, or the installation of malicious software.

Technical details

A heap-based buffer overflow (CWE-122) exists in the Microsoft Windows Media Foundation framework. The vulnerability is triggered when the component fails to properly validate or handle specific data within a media file, leading to memory corruption. While the attack vector is local, it requires user interaction (UI:R), typically involving a victim opening a malicious file or visiting a website hosting malicious media content. Successful exploitation allows for arbitrary code execution with the privileges of the logged-in user. Microsoft has released security updates to address this issue across affected Windows and Windows Server versions.

Affected products

  • Microsoft Windows 10 Versions 1607, 1809, 21H2, 22H2
  • Microsoft Windows 11 Versions 24H2, 25H2, 26H1
  • Microsoft Windows Server 2012 All editions

Timeline

  • 2026-07-14: disclosed
  • 2026-07-14: advisory

References

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