CVE-2025-32717: Heap-based Buffer Overflow in Microsoft Office Word Leading to Unauthorized Code Execution

Overview

CVE-2025-32717 is a significant vulnerability found in the widely used software Microsoft Office Word. This flaw allows an attacker to exploit a heap-based buffer overflow to execute code locally on the victim’s system. This vulnerability is of particular concern due to the prevalence of Microsoft Office Word in both personal and professional environments, making a broad range of users potentially exposed to this security risk.
A successful exploit of this vulnerability could lead to a system compromise or data leakage, posing a serious threat to the confidentiality, integrity, and availability of data. Given the CVSS Severity Score of 8.4, it’s clear that this vulnerability needs immediate attention and mitigation.

Vulnerability Summary

CVE ID: CVE-2025-32717
Severity: High (8.4)
Attack Vector: Local
Privileges Required: None
User Interaction: Required
Impact: System compromise or data leakage

Affected Products

Product | Affected Versions

Microsoft Office Word | Versions prior to the latest patch

How the Exploit Works

The exploit takes advantage of a heap-based buffer overflow vulnerability in Microsoft Office Word. An attacker would craft a malicious Word document that, when opened, would overflow the buffer and allow the attacker to execute arbitrary code on the victim’s system. This code could then potentially compromise the system or lead to data leakage.

Conceptual Example Code

Consider the following
conceptual
pseudocode example of how this vulnerability might be exploited:

// Construct malicious Word document
WordDocument maliciousDoc = new WordDocument();
// Create a buffer overflow in the document
maliciousDoc.addOverflowingBuffer();
// Add arbitrary code to be executed upon overflow
maliciousDoc.addCode("...");
// Send the document to the victim
sendDocument(maliciousDoc, "victim@example.com");

In this pseudocode, an overflowing buffer is added to a Word document. This overflowing buffer is specifically crafted to trigger the heap-based buffer overflow vulnerability. The document also includes arbitrary code that will be executed upon the overflow. The document is then sent to a potential victim.

Mitigation Guidance

Users are strongly advised to apply the patch provided by Microsoft as soon as possible. Until the patch is applied, users can use a Web Application Firewall (WAF) or an Intrusion Detection System (IDS) as a temporary mitigation measure. Regularly updating and patching software is a crucial aspect of maintaining cybersecurity and should never be overlooked.