Arbitrary file upload vulnerability remains a significant security threat to web applications that allow users to upload files. In this post, we take an in-depth look at CVE-2024-35570, a vulnerability in the inxedu v2..6 that results from an arbitrary file upload. We will discuss how attackers can exploit this vulnerability to execute arbitrary code and show a code snippet that illustrates it. Furthermore, we will provide links to the original references and go over the essential exploit details.

Background

inxedu is an open-source online learning platform designed for educational institutions. It is built using Java and provides various features, including course management, user management, and multimedia support. In version 2..6, a critical security vulnerability CVE-2024-35570 has been identified. CVE stands for Common Vulnerabilities and Exposures and is a publicly known cybersecurity vulnerability database.

Vulnerability Details

The arbitrary file upload vulnerability was found in the ImageUploadController.class component of inxedu v2..6. This vulnerability allows attackers to upload crafted JSP files to execute arbitrary code on the server. JSP is short for JavaServer Pages, which is a web framework designed for writing dynamic HTML and XML content using Java.

An attacker can exploit this vulnerability to gain unauthorized access to sensitive data or execute malicious code that, in turn, would compromise the entire web application. The vulnerability occurs due to insufficient validation of the file type before accepting the uploaded files. In this case, the application accepts and processes JSP files, which can potentially contain malicious code.

Code Snippet

The vulnerability is present in the "upload" method found in the ImageUploadController.class component of inxedu v2..6. The following is a simplified code snippet representing the relevant part of the method:

@RequestMapping("/upload")
public String upload(
        HttpServletRequest request, HttpServletResponse response){
    
    if (!checkFileValidation(request)){
        return "error";
    }
    
    // File upload logic follows...
}

The checkFileValidation(request) method is responsible for verifying if the uploaded file is valid. However, this method does not adequately validate the file type, allowing an attacker to bypass this check by crafting a JSP file that contains malicious code.

The attacker creates a specially crafted JSP file containing the malicious code.

2. The attacker uploads the JSP file using the upload feature available on the affected inxedu v2..6 platform, bypassing the file validation process.
3. Once the JSP file is uploaded, the attacker can execute the malicious code by directly accessing the URL of the uploaded JSP file.
4. The executed code could allow the attacker to compromise the entire web application, depending on the nature of the malicious code.

Original References

- The original CVE information can be found in the NIST National Vulnerability Database (NVD) under CVE-2024-35570.
- An advisory detailing the vulnerability in the inxedu v2..6 is available on Exploit Database.

Conclusion

CVE-2024-35570 is a critical vulnerability in inxedu v2..6. It potentially allows attackers to upload arbitrary files, including those containing malicious code, and execute them on the server. This exploitation can result in unauthorized access, compromise the web application, or gain access to sensitive information. It is essential to validate the files' type appropriately during the upload process and ensure that only intended files are accepted and processed, thereby preventing any potential breaches due to CVE-2024-35570.

Timeline

Published on: 05/23/2024 19:16:01 UTC
Last modified on: 08/26/2024 16:35:08 UTC