CVE-2025-54910: Exploiting Heap-based Buffer Overflow in Microsoft Office

Overview

The vulnerability in question, CVE-2025-54910, is a serious security flaw in Microsoft Office that could allow an unauthorized attacker to execute code locally. This vulnerability is particularly dangerous because it affects a wide range of users, given the wide usage of Microsoft Office across various industries worldwide. The potential impact of this vulnerability is significant, as it could lead to system compromise or data leakage.

Vulnerability Summary

CVE ID: CVE-2025-54910
Severity: High (CVSS 8.4)
Attack Vector: Local
Privileges Required: None
User Interaction: Required
Impact: Unauthorized code execution, potential system compromise, and data leakage

Affected Products

Product | Affected Versions

Microsoft Office | All versions prior to the latest security patch

How the Exploit Works

The vulnerability lies in the way Microsoft Office handles memory allocation for certain tasks. By creating a specially crafted document, an attacker can cause a heap-based buffer overflow when the document is opened. This overflow can allow the attacker to execute arbitrary code in the context of the current user. If the current user is logged on with administrative rights, the attacker could take control of the affected system, leading to system compromise or data leakage.

Conceptual Example Code

Here is a conceptual example of how the vulnerability might be exploited. This is pseudocode for creating a malicious document:

Create new Document
Embed malicious code into Document properties
Save Document as .docx

When the document is opened, the malicious code is executed causing a heap-based buffer overflow, which could allow further malicious actions.
It is important to note that this is a simplified example. In reality, exploiting this vulnerability would require a deep understanding of memory management and the inner workings of Microsoft Office.

Recommended Mitigations

Microsoft has released a patch that addresses this vulnerability. Users are strongly advised to update their Microsoft Office to the latest version. If the patch cannot be applied immediately, users can consider using a Web Application Firewall (WAF) or Intrusion Detection System (IDS) to detect and prevent attempts to exploit this vulnerability. These are temporary mitigations and the patch should be applied as soon as possible.