# CVE-2026-111306: Microsoft Word heap-based buffer overflow

Source: https://junglewise.ai/threats/cve-2026-111306-heap-based-buffer-overflow-in-microsoft-office-word-allows-an  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-11-10. Updated: 2026-11-10  
License: CC BY 4.0 with a link back

CVE-2026-111306 · Severity: high · CVSS 8.8 · Published 2026-11-10

Microsoft Word contains a heap-based buffer overflow vulnerability that can be exploited by an attacker to execute arbitrary code on a user's computer. An attacker could deliver a malicious Word document that, when opened, runs code with the privileges of the user, potentially leading to data theft, installation of malware, or system compromise.

Technologies: [Microsoft Word](https://junglewise.ai/threats/technologies/word). Vendors: [Microsoft](https://junglewise.ai/threats/vendors/microsoft).

## Quick answers

**Is CVE-2026-111306 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-111306 being exploited in the wild.

**How severe is CVE-2026-111306?** High severity, with a CVSS score of 8.8, published 10 November 2026.

**Which products and versions are affected?** Microsoft Word.

**Is there a fix for CVE-2026-111306?** 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-2026-111306 attacked?** It is attacked over the network, in a software library.

**Am I affected by CVE-2026-111306?** Check whether you run Microsoft Word. 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 exists in Microsoft Word's document processing logic, allowing code execution via a specially crafted document. The vulnerability requires user interaction (opening a malicious document) but does not require authentication. An attacker can achieve arbitrary code execution in the context of the affected user.

## Affected products

- Microsoft Word

## Timeline

- 2026-11-10: disclosed

## References

- [https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-111306](https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-111306)

## Related threats

- [Microsoft Word use-after-free remote code execution](https://junglewise.ai/threats/cve-2026-112735-use-after-free-in-microsoft-office-word-allows-an-unauthorized)
- [Microsoft Word heap-based buffer overflow](https://junglewise.ai/threats/cve-2026-112724-heap-based-buffer-overflow-in-microsoft-office-word-allows-an)
- [Microsoft Word heap-based buffer overflow](https://junglewise.ai/threats/cve-2026-112716-heap-based-buffer-overflow-in-microsoft-office-word-allows-an)
- [Microsoft Office Word heap-based buffer overflow](https://junglewise.ai/threats/cve-2026-110056-heap-based-buffer-overflow-in-microsoft-office-word-allows-an)
- [Microsoft Word heap-based buffer overflow](https://junglewise.ai/threats/cve-2026-110049-heap-based-buffer-overflow-in-microsoft-office-word-allows-an)