Heap-based Buffer Overflow in Microsoft Office PowerPoint by Microsoft
CVE-2026-55123

7.8HIGH

Key Information:

Vendor

Microsoft
Status
Microsoft 365 Apps For Enterprise
Microsoft Office 2019
Microsoft Office 365 For Mac
Microsoft Office Ltsc 2021
Vendor
CVE Published:
14 July 2026

What is CVE-2026-55123?

A heap-based buffer overflow vulnerability in Microsoft Office PowerPoint can be exploited by an unauthorized attacker to execute arbitrary code on targeted systems. This weakness arises when handling specially crafted PowerPoint files, potentially allowing the attacker to execute malicious code locally. Users are urged to apply the latest security updates to mitigate this risk.

Affected Version(s)

Microsoft 365 Apps for Enterprise 32-bit Systems 16.0.1

Microsoft Office 2019 32-bit Systems 19.0.0

Microsoft Office 365 for Mac 1.0.0 < 16.111.26071215

References

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

CVSS V3.1

Score:
7.8
Severity:
HIGH
Confidentiality:
High
Integrity:
High
Availability:
High
Attack Vector:
Local
Attack Complexity:
Low
Privileges Required:
None
User Interaction:
Required
Scope:
Unchanged

Timeline

  • Vulnerability published

  • Vulnerability Reserved

.