What is CVE-2026-69477?

CVE-2026-69477 is a high-severity vulnerability in Microsoft 365 Apps For Enterprise, classified under Heap-based Buffer Overflow. CVSS score: 7.3/10. Published 2026-09-08.

How severe is CVE-2026-69477?

High severity. CVSS v3 base score is 7.3 out of 10.

Buffer overflow in Microsoft 365 Apps For Enterprise

CVE-2026-69477

Heap-based buffer overflow in Microsoft Office Access allows an authorized attacker to execute code locally.

Vulnerability class: Buffer Overflow

CVSS v3 metric

CVSS v3 base score 7.3 (High). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:H.

Affected products

Microsoft 365 Apps For Enterprise
Microsoft Access 2016
Microsoft Access 2016 (32-bit Edition)
Microsoft Office 2019
Microsoft Office Ltsc 2021
Microsoft Office Ltsc 2024

Weakness classification (CWE)

CWE-122 — Heap-based Buffer Overflow

References

secure@microsoft.com (vendor-advisory, patch)

Frequently asked questions

What is CVE-2026-69477?: CVE-2026-69477 is a high-severity vulnerability in Microsoft 365 Apps For Enterprise, classified under Heap-based Buffer Overflow. CVSS score: 7.3/10. Published 2026-09-08.
How severe is CVE-2026-69477?: High severity. CVSS v3 base score is 7.3 out of 10.