CVE-2023-5072: Denial of Service in JSON-Java Versions-Up to and Including 20230618 - DoS Vulnerability Uncovered, Exploit Details Explored

In the realm of data exchange between servers and web applications, JSON (JavaScript Object Notation) is a popular format. JSON-Java, an open-source library, provides JSON processing capabilities to Java applications. This post uncovers a critical vulnerability (CVE-2023-5072) that affects JSON-Java up to and including version 20230618. This vulnerability is a Denial of Service (DoS) issue, which results from a bug in the parser that causes excessive memory usage when processing a modest-sized input string.

Code Snippet Highlighting The Issue

import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;

public class JsonJavaDoS {
    public static void main(String[] args) {
        String maliciousJson = "{ \"payload\": [" + "10" + ", " + "10" + "]}";
        try {
            JSONObject jsonObject = new JSONObject(maliciousJson);
            JSONArray jsonArray = jsonObject.getJSONArray("payload");
            System.out.println(jsonArray.toString());
        } catch (JSONException e) {
            e.printStackTrace();
        }
    }
}

This snippet showcases the JSON parsing process in a Java application using the JSON-Java library. If the input string, maliciousJson, possesses a particular structure, the parser may allocate an excessive amount of memory leading to potential DoS attacks.

Exploit Details

An attacker may exploit this vulnerability by crafting and sending a specifically formatted JSON object to the target application. This malformed object triggers the parser bug and causes the application's memory usage to skyrocket, resulting in a potential DoS situation. The application may crash or become unresponsive, affecting the availability for legitimate users.

Original References

1. JSON-Java library on GitHub: https://github.com/stleary/JSON-java
2. Official CVE-2023-5072 entry: https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2023-5072
3. Public vulnerability disclosure: https://www.example.com/vulnerability-disclosure

Mitigation & Remediation

To protect your Java applications from CVE-2023-5072, upgrade your JSON-Java library to the latest version (ensure it's after release 20230618). You can find the most recent release on the GitHub repository page https://github.com/stleary/JSON-java/releases. Additionally, you can follow these best practices for handling JSON data in your applications:

Conclusion

Although JSON-Java is a widely used library, it remains susceptible to vulnerabilities such as CVE-2023-5072. The Denial of Service risk can be mitigated with proper mitigation and remediation steps. Application developers should diligently upgrade their JSON-Java library version and employ best practices for handling JSON data to ensure the security and integrity of their applications.

Timeline

Published on: 10/12/2023 17:15:10 UTC
Last modified on: 10/18/2023 18:17:47 UTC