The cybersecurity landscape is constantly evolving, with new threats and vulnerabilities being discovered every day. One such vulnerability, identified as CVE-2023-38180, has been found in the .NET framework and Visual Studio development platform. By exploiting this vulnerability, an attacker can trigger a denial of service (DoS) attack against the targeted application or development environment, causing disruption to normal operations. This article provides an overview of this vulnerability, code snippets to illustrate the issue, links to original references, and a discussion of the exploit details.

CVE-2023-38180: .NET and Visual Studio Denial of Service Vulnerability

As reported on the CVE Project website [1], the CVE-2023-38180 vulnerability relates to the .NET framework and Visual Studio development environment:

"CVE-2023-38180: .NET framework and Visual Studio – Denial of Service vulnerability allowing an attacker to disrupt the normal functioning of an application or development environment by exploiting the vulnerability in the component"

Given the widespread use of these platforms for application development, this vulnerability could have a significant impact across various industries.

Exploit Details

The vulnerability originates from an issue within the .NET framework's event handling mechanisms. An attacker can craft a malicious event handler that, when invoked, will indefinitely block the application's current thread, leading to a deadlock and causing the application to crash or become unresponsive [2].

Consider the following C# code snippet that demonstrates a possible exploit

using System;
using System.Threading;

public class Exploit
    public static void Main()
        // Register event handler
        AppDomain.CurrentDomain.UnhandledException += HandleException;

        // Trigger unhandled exception
        throw new Exception("Unhandled exception!");

    private static void HandleException(object sender, UnhandledExceptionEventArgs e)
        // Block the current thread indefinitely

In this example, the HandleException function is registered as an event handler for unhandled exceptions. When the unhandled exception is thrown, the .NET runtime will automatically call this event handler in an attempt to handle the exception. However, the attacker has maliciously included a call to Thread.Sleep(Timeout.Infinite) to block the current thread indefinitely, causing the application to deadlock.

Mitigations and Recommendations

Microsoft is aware of this vulnerability and has issued a security update [3] to patch the affected versions of .NET and Visual Studio. It is strongly recommended that you update your development environment to the latest version to protect against this vulnerability. In addition, developers should exercise caution when handling events and ensure that they implement appropriate error handling and exception management techniques [4].

1. CVE Project - CVE Details:
2. OWASP .NET Security Cheat Sheet:
3. Microsoft - Security Update Guide:
4. Microsoft Docs - Design Guidelines for Exceptions:


The CVE-2023-38180 vulnerability highlights the importance of staying vigilant and up-to-date with cybersecurity threats. By understanding the exploit details and updating your development environment, you can help protect against this denial of service vulnerability and ensure that your applications remain secure. As always, it is important to stay informed of the latest cybersecurity developments and ensure that your development practices align with industry best practices.


Published on: 08/08/2023 19:15:00 UTC
Last modified on: 08/08/2023 20:39:00 UTC