Heap-based Buffer Overflow in Microsoft Office Outlook by Microsoft
CVE-2026-69629

8.8HIGH

Key Information:

Vendor

Microsoft
Status
Microsoft 365 Apps For Enterprise
Microsoft Office 2019
Microsoft Office Ltsc 2021
Microsoft Office Ltsc 2024
Vendor
CVE Published:
8 September 2026

What is CVE-2026-69629?

A heap-based buffer overflow vulnerability in Microsoft Office Outlook allows attackers to execute arbitrary code over a network. This security flaw can be exploited if an unauthorized user sends a specially crafted email to a targeted Outlook user, potentially leading to unauthorized access and control over the affected system. It is crucial for users to apply relevant security patches to mitigate the risk associated with this vulnerability.

Affected Version(s)

Microsoft 365 Apps for Enterprise 32-bit Systems 16.0.1 < 16.0.20326.20138

Microsoft Office 2019 32-bit Systems 19.0.0 < 16.0.10417.20207

Microsoft Office LTSC 2021 32-bit Systems 16.0.1 < 16.0.14334.20906

References

https://msrc.microsoft.com/update-guide/vulnerability/CVE...
vendor-advisorypatch

CVSS V3.1

Score:
8.8
Severity:
HIGH
Confidentiality:
High
Integrity:
High
Availability:
High
Attack Vector:
Network
Attack Complexity:
Low
Privileges Required:
None
User Interaction:
Required
Scope:
Unchanged

Timeline

  • Vulnerability published

  • Vulnerability Reserved

.