CVE-2022-2791: Emerson Electric's Proficy Machine Edition Vulnerability - Unrestricted Upload of File with Dangerous Type

Emerson Electric's Proficy Machine Edition (PME) Version 9.00 and earlier versions have been discovered to be vulnerable to CWE-434, which is an unrestricted upload of a file with a dangerous type. Attackers taking advantage of this vulnerability may upload malicious files into the Programmable Logic Controller (PLC) logic folder, giving them the ability to compromise systems and networks.

In this post, we will dive into the details of the vulnerability (CVE-2022-2791), provide example code snippets showcasing the exploit, and discuss mitigation steps. We will also provide links to the original references and related resources for further reading.

Exploit Details

The CWE-434 vulnerability opens the door for an attacker to upload any file type into the PLC logic folder without any restrictions, potentially allowing the attacker to write/execute arbitrary code within the PLC. By exploiting this vulnerability, an attacker gains unauthorized access to, and control over, the PLC and any connected systems.

Example Code Snippet

Below is an example of a Python code snippet depicting how an attacker could potentially exploit CVE-2022-2791:

import requests

# Replace 'target_url' with the actual URL of the vulnerable PME system
target_url = 'http://vulnerable-pme-system/';
headers = {'Content-Type': 'multipart/form-data'}

# Replace 'malicious_file_path' with the path of the malicious file to be uploaded
malicious_file_path = 'path/to/malicious/file'
with open(malicious_file_path, 'rb') as file:
    files = {'file': file}
    requests.post(target_url, headers=headers, files=files)

Please note that the code snippet provided above is for educational purposes only and should not be used for malicious intent.

Original References

1. NIST National Vulnerability Database (NVD) Entry for CVE-2022-2791: https://nvd.nist.gov/vuln/detail/CVE-2022-2791
2. Common Vulnerabilities and Exposures (CVE) Details: https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2022-2791

To mitigate this vulnerability, users of Proficy Machine Edition Version 9.00 and earlier should

1. Upgrade to Proficy Machine Edition Version 9.10 or later, which contains a fix for this vulnerability. The latest version can be found on the Emerson Electric website: https://www.emerson.com/en-us/automation-solutions/plc-pac
2. Implement proper access controls to ensure that only authorized personnel have access to the PME interface.
3. Regularly monitor and audit the files within the PLC logic folder to detect any unauthorized changes or file uploads.

Conclusion

The CWE-434 unrestricted upload of file with dangerous type vulnerability found in Emerson Electric's Proficy Machine Edition Version 9.00 and earlier poses a significant risk to users' systems and networks. By exploiting this vulnerability, attackers may gain unauthorized access to, and control over, the PLC and connected systems. To protect against this threat, it is important to follow the mitigation steps outlined above and stay informed of any updates and patches available.

Timeline

Published on: 11/22/2022 20:15:00 UTC
Last modified on: 11/26/2022 03:32:00 UTC