# CVE-2026-70130: Microsoft Office heap-based buffer overflow

Source: https://junglewise.ai/threats/cve-2026-70130-microsoft-office-heap-based-buffer-overflow  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-08-11. Updated: 2026-09-25  
License: CC BY 4.0 with a link back

CVE-2026-70130 · Severity: high · CVSS 8.4 · Published 2026-08-11

Microsoft Office is a widely used productivity suite that processes documents and spreadsheets. A heap-based buffer overflow vulnerability in Office allows an attacker with local access to execute arbitrary code with the privileges of the user running the application, potentially leading to data theft, malware installation, or system compromise.

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

## Quick answers

**Is CVE-2026-70130 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-70130 being exploited in the wild.

**How severe is CVE-2026-70130?** High severity, with a CVSS score of 8.4, published 11 August 2026.

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

**Is there a fix for CVE-2026-70130?** 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-2026-70130 attacked?** It is attacked with local access, in a web application.

**Am I affected by CVE-2026-70130?** 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

A heap-based buffer overflow exists in Microsoft Office, allowing local code execution. The vulnerability is triggered through a maliciously crafted Office document; an attacker with local system access or who can trick a user into opening a malicious file can exploit this flaw to overwrite heap memory and execute arbitrary code. The attack requires user interaction (opening a document) and local or adjacent network access. No known active exploitation in the wild at the time of publication. Patches are expected to be available through Microsoft's regular security update cycle.

## Affected products

- Microsoft Office

## Timeline

- 2026-08-11: disclosed

## References

- [https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-70130](https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-70130)

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