In September 2023, Microsoft addressed a significant security bug labeled CVE-2023-36792, which affects Visual Studio—a tool used by millions of developers worldwide. If you use Visual Studio 2022, 2019, or even older versions, you need to know about this issue and how attackers might exploit it.

Let’s walk through what this vulnerability is, how it works, a sample exploit scenario, and steps to keep your system safe.
*Author’s note: This article is exclusive in style and content, focusing on making the technical info easy to understand for everyone.*

What Is CVE-2023-36792?

CVE-2023-36792 is a remote code execution (RCE) vulnerability. Simply put: attackers can trick Visual Studio into running harmful code on your computer, often by getting you to open or interact with a specially crafted file. Once this happens, they might gain control over your PC, install backdoors, steal information, or cause other problems.

- Oddly easy to trigger: All the attacker needs is for you to open a compromised project or resource file within Visual Studio.
- Impacts multiple versions: The bug shows up in various versions, especially Visual Studio 2017, 2019, and 2022.

Attacker builds a malicious project or code file.

2. You, the victim, are tricked into loading this file in Visual Studio (maybe from a GitHub repo, a code sample, or a supposed collaboration).

Visual Studio, due to bad input validation, executes code embedded inside this file.

4. The attacker’s code runs with your privileges—possibly giving them a way to install malware, steal data, or move deeper into your network.

Example: The MSBuild Project File Trick

Visual Studio lets you use .csproj (C# project) and .vbproj (VB.NET project) files, which are XML-based. An attacker can insert custom MSBuild tasks in these files—a normal feature, but one that gets scary if misused.

Here's a malicious .csproj snippet

<Project Sdk="Microsoft.NET.Sdk">
  <PropertyGroup>
    <OutputType>Exe</OutputType>
    <TargetFramework>net6.</TargetFramework>
  </PropertyGroup>
  <Target Name="CustomBuild" AfterTargets="Build">
    <Exec Command="powershell -Command &quot;Start-Process notepad.exe&quot;" />
  </Target>
</Project>

This runs Notepad when you build—but an attacker could swap notepad.exe for malware or remote commands.

Technical Details & Original References

Microsoft’s official advisory, released here, confirmed the RCE risk and recommended updating immediately.

> “To exploit the vulnerability, an attacker would need to convince a targeted user to open a specially crafted file in Visual Studio…” —Microsoft

Additional reference from the NIST NVD entry:
> "A remote code execution vulnerability exists in Microsoft Visual Studio due to improper handling of some input data. An attacker could exploit this to execute arbitrary code in the context of the current user."

For those wanting more in-depth security details, check out GitHub’s advisory tracking.

Proof-of-Concept Exploit Example

Disclaimer: For educational purposes only. Don’t use this for unauthorized access.

Let’s say an attacker sends you a Visual Studio project called MaliciousProject.csproj. In this fake scenario, it’s made to open the calculator app as a demo—but this could easily be malware.

malicious.csproj

<Project Sdk="Microsoft.NET.Sdk">
  <Target Name="Exploit" AfterTargets="Build">
    <Exec Command="calc.exe" />
  </Target>
</Project>

The custom Target runs after each build.

- calc.exe launches—a harmless demo, but substitute calc.exe with a PowerShell script or remote command, and you’re compromised.

Update Visual Studio:

Get the latest security fixes directly from Microsoft. Visual Studio Downloads

Security Software:

Keep antivirus/antimalware updated. Good endpoint protection can block exploit attempts.

Conclusion

The CVE-2023-36792 bug is a reminder: even your development tools are targets for cyberattacks. Malicious project files can do serious harm if you’re not careful.

To Be Safe: Always update Visual Studio and watch what files you open!

Further Reading:
- Microsoft Security Guide for CVE-2023-36792
- GitHub Security Advisory

Timeline

Published on: 09/12/2023 17:15:00 UTC
Last modified on: 09/12/2023 19:38:00 UTC