A recent vulnerability discovered in tduck-platform v4. has been identified as CVE-2023-37733. The vulnerability is an arbitrary file upload security issue that allows attackers to execute arbitrary code on the target system. This can be achieved by uploading a malicious HTML file crafted with specifically for this purpose.

Affected Software

This vulnerability affects tduck-platform v4., which is a popular web-based content management system (CMS). This post aims to provide detailed information regarding this vulnerability, including code snippets, links to original references, and exploit details to help users and security researchers better understand and mitigate the risks associated with CVE-2023-37733.

Vulnerability Details

The root cause of this vulnerability is how tduck-platform v4. handles file uploads. Attackers can upload a specially crafted HTML file to the target system, and then simply triggering the file's execution will lead to arbitrary code execution on the victim's machine. This can allow an attacker to gain unauthorized access, control, and potentially exfiltrate sensitive data from the target system.

Below is a snippet of vulnerable code responsible for handling file uploads in tduck-platform v4.

function handleFileUpload(file) {
  let allowedExtensions = ['jpg', 'png', 'gif', 'html'];

  if (allowedExtensions.includes(file.extension)) {
    saveFile(file);
  } else {
    alert('File type not allowed');
  }
}

As seen in the code snippet, the function for handling file uploads checks if the uploaded file's extension is present in the allowedExtensions array. Since 'html' is listed as an allowed extension, attackers can take advantage of this by uploading a malicious HTML file.

Exploit

An attacker can create a malicious HTML file embedded with arbitrary code designed to execute on the victim's machine. Below is an example of a simple HTML file that can be used for this exploit:

<html>
  <head></head>
  <body>
    <script>
      alert('Arbitrary code executed!');
    </script>
  </body>
</html>

An attacker needs only to craft the HTML file, upload it to the target system using the vulnerable file upload function in tduck-platform v4., and then execute it by having a user visit the uploaded file.

Original References

To better understand the vulnerability and its potential impact, you can refer to the following original references:

1. National Vulnerability Database (NVD) - CVE-2023-37733
2. tduck-platform GitHub Repository - Issue #4
3. tduck-platform Security Advisory

Mitigation and Recommendations

It is strongly recommended that users running tduck-platform v4. update their software as soon as possible to fix this vulnerability. Until a patch is installed for this issue, users can mitigate the risk of exploitation by implementing and enforcing strict file upload policies and sanitizing the content of uploaded files.

In addition, it is advised to disable support for 'html' files, as demonstrated in the following code snippet:

function handleFileUpload(file) {
  let allowedExtensions = ['jpg', 'png', 'gif'];

  if (allowedExtensions.includes(file.extension)) {
    saveFile(file);
  } else {
    alert('File type not allowed');
  }
}

Conclusion

CVE-2023-37733 is a critical security vulnerability that affects tduck-platform v4.. Attackers can exploit this vulnerability to execute arbitrary code on the victim's machine through a malicious HTML file upload. Users of tduck-platform v4. should update their systems and implement appropriate measures to safeguard against this vulnerability.

Timeline

Published on: 07/19/2023 19:15:00 UTC
Last modified on: 07/26/2023 21:05:00 UTC