# CVE-2026-55038: Microsoft Office Word stack-based buffer overflow

Source: https://junglewise.ai/threats/cve-2026-55038-microsoft-office-word-stack-based-buffer-overflow  
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-2026-55038 · Severity: high · CVSS 7.8 · Published 2026-07-14

A security vulnerability exists in Microsoft Word, the widely used word processing application. An attacker could exploit this flaw by tricking a user into opening a specially crafted document, potentially allowing the attacker to take control of the user's computer. This could lead to the theft of sensitive data, unauthorized software installation, or disruption of business operations.

Technologies: [Microsoft SharePoint Server](https://junglewise.ai/threats/technologies/sharepoint-server), [Microsoft Word](https://junglewise.ai/threats/technologies/word). Vendors: [Microsoft](https://junglewise.ai/threats/vendors/microsoft).

## Quick answers

**Is CVE-2026-55038 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-55038 being exploited in the wild.

**How severe is CVE-2026-55038?** High severity, with a CVSS score of 7.8, published 14 July 2026.

**Which products and versions are affected?** Microsoft Word Microsoft 365 Apps, Office 2019, Office LTSC 2021/2024, SharePoint Server.

**Is there a fix for CVE-2026-55038?** 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-2026-55038 attacked?** It is attacked with local access, in a network appliance.

**Am I affected by CVE-2026-55038?** Check whether you run Microsoft SharePoint Server or Microsoft Word 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 stack-based buffer overflow (CWE-121) exists in Microsoft Office Word. The vulnerability is triggered when the application fails to properly validate input while parsing a document, leading to memory corruption. An attacker can exploit this by convincing a target user to open a malicious Word document. Successful exploitation allows for arbitrary code execution in the context of the current user. The attack vector is local with a requirement for user interaction (UI:R). Microsoft has released security updates to address this issue across affected versions of Office and SharePoint Server.

## Affected products

- Microsoft Office Word Microsoft 365 Apps, Office 2019, Office LTSC 2021/2024, SharePoint Server

## Timeline

- 2026-07-14: disclosed
- 2026-07-14: advisory: Microsoft published the security update guide.

## References

- [https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-55038](https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-55038)

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