Heap-based Buffer Overflow in Microsoft Office by Microsoft
CVE-2026-40363

8.4HIGH

Key Information:

Vendor

Microsoft
Status
Microsoft 365 Apps For Enterprise
Microsoft Office 2016
Microsoft Office 2019
Microsoft Office For Android
Vendor
CVE Published:
12 May 2026

What is CVE-2026-40363?

This vulnerability in Microsoft Office is characterized by a heap-based buffer overflow, which can be exploited by an unauthorized attacker to execute arbitrary code on the affected system. This can allow the attacker to gain local access, potentially leading to unauthorized data manipulation or disclosure. Users are strongly advised to apply the available patches and updates to safeguard their systems from this vulnerability.

Affected Version(s)

Microsoft 365 Apps for Enterprise 32-bit Systems 16.0.1

Microsoft Office 2016 32-bit Systems 16.0.0 < 16.0.5552.1000

Microsoft Office 2019 32-bit Systems 19.0.0

References

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

CVSS V3.1

Score:
8.4
Severity:
HIGH
Confidentiality:
High
Integrity:
High
Availability:
High
Attack Vector:
Local
Attack Complexity:
Low
Privileges Required:
None
User Interaction:
None
Scope:
Unchanged

Timeline

  • Vulnerability published

  • Vulnerability Reserved

.