CVE-2026-69629: Microsoft Office Outlook Remote Code Execution Vulnerability

Overview

Severity

High (CVSS 8.8)

CVSS Vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C

Category

Remote Code Execution

Exploit Status

Not Exploited

Exploitation Likelihood

Less Likely

Patch Tuesday

2026-Sep

Released

2026-09-08

Description

Heap-based buffer overflow in Microsoft Office Outlook allows an unauthorized attacker to execute code over a network.

FAQ

According to the CVSS metric, the attack vector is network (AV:N) and user interaction is required (UI:R). What is the target context of the remote code execution? This attack requires a user to open a specially crafted file from the attacker to initiate remote code execution. Is the Preview Pane an attack vector for this vulnerability? Yes, the Preview Pane is an attack vector.

Affected Products (10)

Microsoft Office

• Microsoft Office 2019 for 32-bit editions
• Microsoft Office 2019 for 64-bit editions
• Microsoft 365 Apps for Enterprise for 32-bit Systems
• Microsoft 365 Apps for Enterprise for 64-bit Systems
• Microsoft Office LTSC 2021 for 64-bit editions
• Microsoft Office LTSC 2021 for 32-bit editions
• Microsoft Office LTSC 2024 for 32-bit editions
• Microsoft Office LTSC 2024 for 64-bit editions
• Microsoft Outlook 2016 (32-bit edition)
• Microsoft Outlook 2016 (64-bit edition)

Security Updates (1)

• 5002919

Acknowledgments

0ccbbf129444eb66344ccafb92b00df4

Revision History

• 2026-09-08: Information published.