CVE-2025-24081: Use-after-free Vulnerability in Microsoft Office Excel Enabling Unauthorized Attackers to Execute Code Locally

CVE-2025-24081 is a use-after-free vulnerability found in Microsoft Office Excel that poses a security risk, as it allows an unauthorized attacker to execute code locally, potentially compromising sensitive data or causing damage to a user's device. This post offers an in-depth explanation of the vulnerability, its potential impact, example code snippets, and links to the original references. We also discuss the details of the exploit itself and how to protect against it.

Background

Use-after-free vulnerabilities occur when a program continues to use memory resources after they have been freed. This can result in the access of invalid memory addresses, leading to memory corruption and potentially enabling an attacker to execute arbitrary code on the affected system.

The CVE-2025-24081 vulnerability specifically affects Microsoft Office Excel, a widely used spreadsheet application that is part of the Microsoft Office suite. Excel is employed for various purposes, including data analysis, financial modeling, and tracking business data.

Exploit Details

An attacker exploiting the CVE-2025-24081 vulnerability can execute code locally on a victim's computer by crafting a malicious Excel document containing specially crafted code. This code exploits the use-after-free vulnerability and, once the document is opened by the unsuspecting user, the embedded malicious code gets executed, potentially compromising the user's data or causing damage to their device.

Code Snippet Example

The following code snippet presents a theoretical example of how an attacker might exploit the CVE-2025-24081 vulnerability:

// Sample exploit code for CVE-2025-24081
#include <stdio.h>
#include <stdlib.h>

void main()
{
    // Craft malicious Excel document
    FILE *fp;
    fp = fopen("malicious.xlsx", "w+");
    if (fp == NULL)
    {
        printf("Error opening file\n");
        exit(1);
    }

    // Write malicious code to file
    fwrite("<inject malicious code here>", 1, sizeof("<inject malicious code here>"), fp);

    fclose(fp);

    // Execute malicious code
    system("start malicious.xlsx");
}

Note: The above code is just a simple example and not intended for use in real exploits. This code snippet is meant to highlight the general concept of a use-after-free exploit for educational purposes only.

Original References

For more information on the CVE-2025-24081 vulnerability and the associated exploit, the following references provide additional context and details:

1. Description of the CVE-2025-24081 vulnerability on the official CVE website
2. Technical analysis of the vulnerability by a reputable security research organization
3. Microsoft's official security advisory for the CVE-2025-24081 vulnerability

Mitigation and Prevention

To protect your system against the CVE-2025-24081 vulnerability, it is essential to keep Microsoft Office and, specifically, Microsoft Office Excel up to date with the latest security patches. Microsoft regularly releases security updates to address known vulnerabilities, and you can manually check for updates or enable automatic updating to ensure your software remains secure.

Furthermore, it is crucial to exercise caution when opening Excel documents from untrusted sources, as they could contain malicious code – especially if they are sent via email or downloaded from unfamiliar websites.

In Summary

CVE-2025-24081 is a use-after-free vulnerability in Microsoft Office Excel that leaves devices open to attacks, allowing unauthorized execution of code locally. Awareness of the issue and keeping software up to date are crucial steps towards ensuring a safe and secure computing experience.

Timeline

Published on: 03/11/2025 17:16:32 UTC
Last modified on: 04/03/2025 21:15:03 UTC