A recently discovered vulnerability, CVE-2024-36053, was found affecting the mintupload package through the 4.2. version for Linux Mint. This issue is due to service-name mishandling which leads to command injection, impacting three key functions: check_connection, drop_data_received_cb, and Service.remove.

In this blog post, we will take a deep dive into the details of this vulnerability, including a breakdown of the code snippet and references to original sources. Furthermore, we'll dissect how the exploit works and how a user can modify a service name in a ~/.linuxmint/mintUpload/services/service file.

The Vulnerability - CVE-2024-36053

The vulnerability's origin lies in the service-name handling process in the mintupload package. Specifically, it affects the check_connection, drop_data_received_cb, and Service.remove functions. This vulnerability allows an attacker to inject shell metacharacters and execute arbitrary commands on the victim's system through command injection.

Code Snippet

Examining the code snippet in the context of the select-function function, we can identify a key component that contributes to the vulnerability:

def check_connection(self):
    ...
    command = "ping -c 1 " + self.server
    ...
    pipe = Popen(command, shell=True, stdout=PIPE, stderr=PIPE)
    ...

In this example, the command "ping -c 1" is concatenated with the user-controlled variable 'self.server,' which is taken from the service name in the service file without proper sanitization or validation. Due to this lack of sanitization, an attacker could exploit this vulnerability by injecting shell metacharacters (e.g., '&', '|', ';') into the service name.

Original References

The issue was initially reported on the Linux Mint GitHub repository, where the vulnerability was assigned the identifier CVE-2024-36053. You can find more information and detailed discussions about the vulnerability report through the following links:

- Linux Mint GitHub Issue #50
- CVE-2024-36053 | CVE Details
- National Vulnerability Database (NVD) - CVE-2024-36053

Exploiting the Vulnerability

An example of exploiting this issue would involve an attacker modifying a service file located at ~/.linuxmint/mintUpload/services/service. By injecting shell metacharacters into the service name and then launching the mintupload application, the attacker could execute arbitrary commands with the user's privileges.

Here's a sample proof-of-concept (PoC) that demonstrates how to exploit the vulnerability

1. Create a file called 'malicious.service' in the services directory: ~/.linuxmint/mintUpload/services/

`

service_name=MALICIOUS&touch~/DEMO_EXPLOITED_FILE;

password=pass

directory=/some/dir

Save the file and launch the 'mintupload' application.

4. As a result, a new file called 'DEMO_EXPLOITED_FILE' will be created in the user's home directory, proving that an arbitrary command has been executed.

Conclusion

CVE-2024-36053 is a serious vulnerability present in the mintupload package up to version 4.2. for Linux Mint. This issue stems from mishandling service-names in the check_connection, drop_data_received_cb, and Service.remove functions, which can ultimately lead to command injection via shell metacharacters. To protect yourself from potential exploits, apply any available patches and updates for your mintupload package, practice proper file handling, and implement the Principle of Least Privilege.

Stay vigilant, and always keep a watchful eye on your system's security!

Timeline

Published on: 05/19/2024 16:15:45 UTC
Last modified on: 07/03/2024 02:02:43 UTC