CVE-2024-27447: Understanding the Vulnerability and Exploit in Pretix before 2024.1.1

A new cybersecurity vulnerability has been discovered and assigned the CVE identifier CVE-2024-27447. This vulnerability exists in the Pretix event management software that is widely used by organizations to manage event registration, ticketing, invoicing, and more. Researchers found that the vulnerability can cause Pretix versions before 2024.1.1 to mishandle file validation, which exposes users' data and systems to potential cyberattacks. In this article, we will discuss the details of this vulnerability, examine how it can be exploited, and explore a code snippet pertaining to the vulnerability. We will also provide links to the original references for those interested in further research.

Vulnerability Details

Pretix before 2024.1.1 suffers from a file validation issue that may allow an attacker to upload malicious files and bypass security checks in place. The vulnerability lies in the way Pretix handles file validation, making it possible for an attacker to present a fake file type and bypass the file checking mechanisms. Pretix's intended security measure is to limit the types of files that can be uploaded, but due to the mishandling of file validation, these restrictions become ineffective, allowing an adversary to upload files that should have been denied.

To exploit this vulnerability, an attacker could follow these steps

1. Modify the metadata of a malicious file to appear as a legitimate file type (e.g., change a .exe file to appear as a .jpeg image).

Use a crafted request to upload the malicious file to the Pretix instance.

3. Once the malicious file is uploaded, the attacker can execute it, leading to unauthorized access or control over the affected system.

This exploit has the potential to cause significant damage, as attackers can gain unauthorized access to the user's system, manipulate data, and compromise sensitive information.

Code Snippet

The following simple Python script demonstrates how an attacker might manipulate a file's metadata to bypass Pretix's file validation checks:

import os

def spoof_file_type(file_path, new_file_name):
    with open(file_path, "rb") as original_file:
        original_data = original_file.read()

    with open(new_file_name, "wb") as spoofed_file:
        spoofed_file.write(b"\xFF\xD8")  # Add JPEG magic bytes
        spoofed_file.write(original_data)

if __name__ == "__main__":
    file_path = "malicious_exe_path"
    new_file_name = "spoofed_jpeg_path"
    spoof_file_type(file_path, new_file_name)

Original References

For more information about CVE-2024-27447 and the discovered vulnerability in Pretix, refer to the following resources:

1. CVE Details: A detailed vulnerability description can be found on the Mitre Corporation's CVE database: CVE-2024-27447
2. Pretix Changelog: The Pretix changelog references the vulnerability and its resolution in version 2024.1.1: Pretix 2024.1.1 Changelog
3. National Vulnerability Database: The US NIST's reference page for the vulnerability can be found here: NVD - CVE-2024-27447

Conclusion

This article has provided an overview of CVE-2024-27447, a vulnerability affecting Pretix versions before 2024.1.1. We discussed the vulnerability involved in Pretix's mishandling of file validation, examined a potential exploit, and shared a code snippet demonstrating the vulnerability. It is essential for Pretix users to update to version 2024.1.1 or later to ensure their systems are patched against this vulnerability.

Timeline

Published on: 02/26/2024 16:28:00 UTC
Last modified on: 08/05/2024 16:35:07 UTC