CVE-2026-81399

Buffer over-read in Microsoft Office Excel allows an unauthorized attacker to disclose information locally.

Score

CVSS 3.1 5.5 Medium

Status

Analyzed - secure@microsoft.com

Published

2026-09-08

Last modified

2026-10-14

Weaknesses

CWE-126

Affected products

• 365 Apps (Microsoft)
• Excel (Microsoft)
• Excel 2016 (Microsoft)
• Microsoft 365 (Microsoft)
• Office 2016 (Microsoft)
• Office 2019 (Microsoft)
• Office 2021 (Microsoft)
• Office 2024 (Microsoft)
• Office 365 (Microsoft)
• Office Macos 2021 (Microsoft)
• Office Macos 2024 (Microsoft)

References

• https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-81399