# CVE-2026-80078: Microsoft Office out-of-bounds read

Source: https://junglewise.ai/threats/cve-2026-80078-microsoft-office-out-of-bounds-read  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-09-08. Updated: 2026-09-26  
License: CC BY 4.0 with a link back

CVE-2026-80078 · Severity: medium · CVSS 6.5 · Published 2026-09-08

Microsoft Office contains an out-of-bounds read vulnerability that allows an attacker to disclose sensitive information through a network connection. An attacker can exploit this flaw to read data from memory that should not be accessible, potentially exposing confidential documents or user information. No active exploitation in the wild has been reported.

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

## Quick answers

**Is CVE-2026-80078 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-80078 being exploited in the wild.

**How severe is CVE-2026-80078?** Medium severity, with a CVSS score of 6.5, published 8 September 2026.

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

**Is there a fix for CVE-2026-80078?** 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-2026-80078 attacked?** It is attacked over the network, in a web application.

**Am I affected by CVE-2026-80078?** Check whether you run Microsoft Office. 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

The vulnerability is an out-of-bounds read in Microsoft Office, a memory safety issue where the application reads data beyond the boundaries of allocated memory. This flaw can be triggered over a network, allowing an unauthenticated attacker to craft a malicious Office document or network message that causes the application to leak sensitive data from process memory. The vulnerability enables information disclosure but does not directly allow code execution or unauthorized modification. Microsoft has issued security updates to address this issue.

## Affected products

- Microsoft Office

## Timeline

- 2026-09-08: disclosed

## References

- [https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-80078](https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-80078)

## Related threats

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- [Microsoft Office UI security feature bypass](https://junglewise.ai/threats/cve-2026-119998-product-ui-does-not-warn-user-of-unsafe-actions-in-microsoft)
- [Microsoft Office heap-based buffer overflow](https://junglewise.ai/threats/cve-2026-116717-heap-based-buffer-overflow-in-microsoft-office-allows-an)