Heap-based Buffer Overflow in Microsoft Excel by Microsoft
CVE-2025-29979

7.8HIGH

Key Information:

Vendor

Microsoft
Status
Office Online Server
Microsoft Office 2019
Microsoft 365 Apps For Enterprise
Microsoft Office Ltsc For Mac 2021
Vendor
CVE Published:
13 May 2025

What is CVE-2025-29979?

A heap-based buffer overflow vulnerability in Microsoft Excel allows an unauthorized attacker to execute arbitrary code on the affected system. This security flaw could be exploited through maliciously crafted files, potentially giving attackers control over the machine. Users are urged to apply the latest security updates to mitigate risks associated with unauthorized access and potential data breaches.

Affected Version(s)

Microsoft 365 Apps for Enterprise 32-bit Systems 16.0.1

Microsoft Office 2016 32-bit Systems 16.0.0 < 16.0.5500.1000

Microsoft Office 2019 32-bit Systems 19.0.0

References

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

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

.
CVE-2025-29979 : Heap-based Buffer Overflow in Microsoft Excel by Microsoft