# CVE-2026-54987: Microsoft Windows heap overflow in Windows Overlay Filter

Source: https://junglewise.ai/threats/cve-2026-54987-microsoft-windows-heap-overflow-in-windows-overlay-filter  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-07-14. Updated: 2026-07-14  
License: CC BY 4.0 with a link back

CVE-2026-54987 · Severity: high · CVSS 7.8 · Published 2026-07-14

A security vulnerability has been identified in the Windows Overlay Filter, a component of the Windows operating system. An attacker who already has basic access to a computer could exploit this flaw to gain full administrative control over the system. This could allow them to access sensitive data, install malicious software, or disrupt business operations.

Technologies: [Microsoft Windows 11](https://junglewise.ai/threats/technologies/windows-11), [Microsoft Windows Server 2012 R2](https://junglewise.ai/threats/technologies/windows-server-2012-r2), [Microsoft Windows 10](https://junglewise.ai/threats/technologies/windows-10). Vendors: [Microsoft](https://junglewise.ai/threats/vendors/microsoft).

## Quick answers

**Is CVE-2026-54987 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-54987 being exploited in the wild.

**How severe is CVE-2026-54987?** High severity, with a CVSS score of 7.8, published 14 July 2026.

**Which products and versions are affected?** Microsoft Windows 11 24H2, 25H2, 26H1; Microsoft Windows Server 2012 R2 All versions; Microsoft Windows 10 1607, 1809, 21H2, 22H2.

**Is there a fix for CVE-2026-54987?** No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

**How is CVE-2026-54987 attacked?** It is attacked with local access, in an operating system.

**Am I affected by CVE-2026-54987?** Check whether you run Microsoft Windows 11, Microsoft Windows Server 2012 R2 or Microsoft Windows 10 at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

A heap-based buffer overflow (CWE-122) exists in the Windows Overlay Filter component. The vulnerability is triggered locally by an authenticated user with low privileges (PR:L). By exploiting this memory corruption issue, an attacker can execute arbitrary code with elevated system privileges. The attack does not require user interaction and has a high impact on confidentiality, integrity, and availability. Microsoft has released security updates for various versions of Windows 10, Windows 11, and Windows Server to address this issue.

## Affected products

- Microsoft Windows 10 1607, 1809, 21H2, 22H2
- Microsoft Windows 11 24H2, 25H2, 26H1
- Microsoft Windows Server 2012 R2 All versions

## Timeline

- 2026-07-14: disclosed: Initial publication of the CVE record by Microsoft.
- 2026-07-14: advisory: NVD entry published.

## References

- [https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-54987](https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-54987)

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