Buffer overflow in Microsoft 365 Apps For Enterprise
CVE-2026-50678
Heap-based buffer overflow in Microsoft Office Excel allows an unauthorized attacker to disclose information locally.
Vulnerability class: Buffer Overflow
CVSS v3 metric
CVSS v3 base score 6.6 (Medium). Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:H.
Affected products
- Microsoft 365 Apps For Enterprise — versions 16.0.1
- Microsoft Excel 2016 — versions 16.0.0.0
- Microsoft Office 2019 — versions 19.0.0
- Microsoft Office 365 For Mac — versions 1.0.0
- Microsoft Office Ltsc 2021 — versions 16.0.1
- Microsoft Office Ltsc 2024 — versions 16.0.0
- Microsoft Office Ltsc For Mac 2021 — versions 16.0.1
- Microsoft Office Ltsc For Mac 2024 — versions 16.0.0
- Microsoft Office Online Server — versions 16.0.0.0
Weakness classification (CWE)
References
- secure@microsoft.com (vendor-advisory, patch)
Frequently asked questions
- What is CVE-2026-50678?
- CVE-2026-50678 is a medium-severity vulnerability in Microsoft 365 Apps For Enterprise, classified under Heap-based Buffer Overflow. CVSS score: 6.6/10. Published 2026-07-14.
- How severe is CVE-2026-50678?
- Medium severity. CVSS v3 base score is 6.6 out of 10.