# CVE-2026-105596: Microsoft Office Access heap-based buffer overflow

Source: https://junglewise.ai/threats/cve-2026-105596-heap-based-buffer-overflow-in-microsoft-office-access-allows-an  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-10-13. Updated: 2026-10-16  
License: CC BY 4.0 with a link back

CVE-2026-105596 · Severity: high · CVSS 8.8 · Published 2026-10-13

A heap-based buffer overflow vulnerability in Microsoft Office Access allows an attacker to execute malicious code remotely by sending a specially crafted file over the network. This could lead to complete system compromise, including data theft, installation of malware, or lateral movement within an organization.

Technologies: [Microsoft 365 Apps](https://junglewise.ai/threats/technologies/365-apps), [Microsoft Office 2021](https://junglewise.ai/threats/technologies/office-2021), [Microsoft Office 2024](https://junglewise.ai/threats/technologies/office-2024), [Microsoft Office Access](https://junglewise.ai/threats/technologies/office-access). Vendors: [Microsoft](https://junglewise.ai/threats/vendors/microsoft).

## Quick answers

**Is CVE-2026-105596 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-105596 being exploited in the wild.

**How severe is CVE-2026-105596?** High severity, with a CVSS score of 8.8, published 13 October 2026.

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

**Is there a fix for CVE-2026-105596?** 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-2026-105596 attacked?** It is attacked over the network.

**Am I affected by CVE-2026-105596?** Check whether you run Microsoft 365 Apps, Microsoft Office 2021, Microsoft Office 2024 or one of the others listed. 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 a heap-based buffer overflow in Microsoft Office Access that can be triggered by processing a malformed input, allowing remote code execution without authentication. An attacker needs only network access to deliver a malicious payload; no user interaction beyond opening a file is required. The overflow enables arbitrary code execution with the privileges of the Office process.

## Affected products

- Microsoft Office Access

## References

- [https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-105596](https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-105596)

## Related threats

- [Microsoft Office Access heap-based buffer overflow](https://junglewise.ai/threats/cve-2026-111305-heap-based-buffer-overflow-in-microsoft-office-access-allows-an)
- [Microsoft Office Access heap buffer overflow](https://junglewise.ai/threats/cve-2026-111301-heap-based-buffer-overflow-in-microsoft-office-access-allows-an)
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- [Microsoft Office Access heap buffer overflow](https://junglewise.ai/threats/cve-2026-110058-heap-based-buffer-overflow-in-microsoft-office-access-allows-an)