Microsoft Dynamics GP is a popular accounting and enterprise resource planning (ERP) software used by businesses of all sizes. In February 2022, Microsoft patched a critical remote code execution (RCE) vulnerability in Dynamics GP, tagged as CVE-2022-23274. While the software is often kept inside internal networks, this vulnerability shows that even your internal apps need strong security practices.

This article explains CVE-2022-23274, how attackers could exploit it, and how you can protect your systems. We’ll keep the language simple and make this information easy to understand—even for those who aren’t security professionals. You’ll also find code snippets that show how this bug can be abused in real-world scenarios.

What Is CVE-2022-23274?

This vulnerability allows an attacker to run any code they want on a Microsoft Dynamics GP server without permission. If an attacker can trick a user into opening a malicious Dynamics GP application file (such as a specially crafted .dic or .cnk file), they could take over the entire ERP system, steal sensitive business data, or move deeper into your network.

Affected Version:  
Microsoft Dynamics GP 2018, GP 2013, GP 2016, and possibly earlier versions.

Impact:

Potential full compromise of ERP data

How Does the Vulnerability Work?

Dynamics GP supports importing custom assemblies, dictionaries, and chunk files (.cnk). These files add features but can be abused if GP doesn't properly check them before loading.

The flaw: GP loads these files without strong validation or sandboxing. If an attacker gets their malicious file onto a server or convinces someone to open it, Dynamics GP executes code inside the file.

Exploit Example: Running a Malicious Command

Let's look at a pseudo-code snippet of what could happen inside a malicious chunk file. (Note: For ethical reasons, we’re not sharing live malware code, but this shows the basic concept.)

// Malicious code inside a crafted .cnk file
using System.Diagnostics;

public class Exploit
{
    public static void RunMaliciousPayload()
    {
        // Spawn a reverse shell or download a malicious payload
        Process.Start("cmd.exe", "/c powershell -EncodedCommand <maliciousBase64Payload>");
    }
}

The Dynamics GP engine loads this file, and the malicious RunMaliciousPayload function runs. This opens a command prompt on the victim's machine, which can connect back to the attacker's server or execute any commands.

Real World Attack Steps

1. Reconnaissance: Attacker identifies users running Dynamics GP (via phishing, exploiting a weak VPN, or scanning internal networks).
2. Delivery: Attacker creates a malicious .cnk file, maybe calling it “NewInvoiceModule.cnk,” and sends it via email, Teams, or puts it in a shared folder.
3. Execution: User opens Dynamics GP and loads the file, possibly thinking it's a real module or update.

1. Patch Immediately

Microsoft released security updates for supported Dynamics GP versions in February 2022. Install them!

2. Limit File Sharing and Email Attachments

Block .cnk, .dic, and other GP-related file types in email and file-sharing services.

3. User Education

Train staff about suspicious files and phishing campaigns that might target internal applications like GP.

4. Least Privilege

Don’t let users run GP with admin or Domain Admin rights. Lower privilege means lower risk if a file gets through.

5. Monitor for Unusual Activity

Keep an eye on GP logs and for new files in shared folders.

References and Further Reading

- Microsoft Security Response Center: CVE-2022-23274
- Microsoft Dynamics GP Security Update Guide
- NIST National Vulnerability Database: CVE-2022-23274

Conclusion

CVE-2022-23274 is a strong reminder that enterprise software, even when used on private networks, is a big target for attackers. Always patch your business apps, restrict who can run code, and train your people to spot weird files and phishing attempts. A simple email attachment can lead to a major security incident if you’re not careful.

Stay safe, keep your ERP patched, and spread the word to your IT team!

Timeline

Published on: 02/09/2022 17:15:00 UTC
Last modified on: 02/14/2022 18:39:00 UTC