A critical path traversal vulnerability has been discovered in smanga 3.2.7. This vulnerability allows malicious actors to read files outside the intended directory, leading to unauthorized access to sensitive information or system files. This blog post will explore CVE-2024-34193 in detail by discussing the issue, how it can be exploited, potential impacts, and recommended mitigations. Additionally, code snippets and links to original sources are provided for better comprehension.

Background

smanga (Simple MAnGga delphi) is an open-source manga reading app built using PHP. The vulnerability in question (CVE-2024-34193) affects version 3.2.7 of smanga. The software inadequately filters the file parameter at the PHP/get_file flow.php interface, leading to the path traversal vulnerability.

Details of CVE-2024-34193

PHP/get_file flow.php interface in smanga 3.2.7 does not sanitize user input, which can be exploited to read arbitrary files by supplying a specially crafted file parameter. The vulnerable code snippet is as follows:

$file = $_GET['file'];
if (!empty($file)) {
    $file = realpath($file);
    if (file_exists($file)) {
        readfile($file);
    } else {
        echo "File not found!";
    }
} else {
    echo "No file specified!";
}

The code above gets the file parameter from the URL and calls the realpath() function to resolve the input path, but realpath does not validate or sanitize the input. Consequently, an attacker can supply a crafted file parameter containing relative paths (using ../) to gain access to files outside the intended directory.

Exploiting CVE-2024-34193

To exploit this vulnerability, an attacker can simply supply a malicious URL containing the crafted file parameter with a relative path, like the following:

http://example.com/get_file_flow.php?file=../../../../etc/passwd

With a specially crafted URL like the one above, the attacker bypasses the intended directory and gains unauthorized access to sensitive system files, like the /etc/passwd file in this example.

Potential Impact

While exploiting CVE-2024-34193 may not grant complete control over the system, it does allow unauthorized access to sensitive information. Attackers can use the vulnerability to exfiltrate valuable data, pivot to other system components, or even discover further vulnerabilities in the system.

1. Update smanga to the latest version: This vulnerability affects smanga 3.2.7, so upgrading to a newer version will likely eliminate the issue.
2. Validate user input: Properly sanitize the 'file' parameter by implementing input validation techniques, such as checking for alphanumeric values and restricting the use of special characters (like "../").
3. Limit unauthorized access: Configure your application's access controls to restrict unauthorized users from interacting with sensitive resources.

1. CVE-2024-34193 description: https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2024-34193
2. smanga project GitHub repository: https://github.com/smanga-project/smanga
3. Path traversal vulnerability explanation: https://owasp.org/www-community/attacks/Path_Traversal

Conclusion

The critical path traversal vulnerability (CVE-2024-34193) affecting smanga 3.2.7 highlights the importance of input validation and secure coding practices. Developers should assess and thoroughly test their applications for vulnerabilities, while system administrators should remain vigilant in monitoring for attacks and applying security updates. By being proactive in addressing vulnerabilities, organizations can better protect their applications and data from potential exploitation.

Timeline

Published on: 05/20/2024 18:15:10 UTC
Last modified on: 08/20/2024 15:35:11 UTC