CVE-2022-39944: Deserialization Vulnerability in Apache Linkis <=1.2. with MySQL Connector/J - Remote Code Execution Risk and Mitigation Steps

Security vulnerabilities are a constant concern in the world of software development. The recently discovered CVE-2022-39944 highlights a deserialization vulnerability in Apache Linkis <=1.2. when used in conjunction with the MySQL Connector/J. When exploited, this vulnerability can lead to the potential of remote code execution if an attacker has write access to a database and configures a JDBC EC (Execution Context) with a MySQL data source and malicious parameters. In this post, we will be discussing the details of this vulnerability, along with the recommendations to mitigate possible attacks.

Description of the vulnerability (technical details)

The CVE-2022-39944 vulnerability stems from the improper handling of user-supplied JNDI (Java Naming and Directory Interface) references in the JDBC URLs by the MySQL Connector/J library. This can enable an attacker with write access to a database to insert malicious parameters, leading to a deserialization attack, and potentially remote code execution.

To better illustrate the issue, consider the following sample code snippet demonstrating the JDBC configuration:

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;

public class MySQLConnectionTest {
    public static void main(String[] args) {
        String URL = "jdbc:mysql://localhost/test?user=root&password=admin";

        try {
            Connection connection = DriverManager.getConnection(URL);
            // ...
        } catch (SQLException e) {
            e.printStackTrace();
        }
    }
}

Through this vulnerability, an attacker could potentially alter the 'URL' variable to include malicious parameters that exploit deserialization, leading to remote code execution.

Mitigation steps

Apache Linkis has recognized this vulnerability and recommends updating to version 1.3., which addresses this issue. Additionally, users should blacklist the parameters in the JDBC URLs to further minimize attack vectors.

To update your Apache Linkis to 1.3., follow the official upgrade instructions from the Apache Linkis website.

To further protect your system, consider implementing a proactive approach by blacklisting certain parameters in your JDBC URLs. The following is an example of a basic blacklisting implementation in Java:

public static boolean isURLSafe(String URL) {
    String[] blacklist = { "maliciousParam1", "maliciousParam2" };
    for (String item : blacklist) {
        if (URL.contains(item)) {
            return false;
        }
    }
    return true;
}

public static void main(String[] args) {
    String URL = "jdbc:mysql://localhost/test?user=root&password=admin";
    if (isURLSafe(URL)) {
        // proceed with establishing the connection
    } else {
        // log or handle unsafe URL
    }
}

In conclusion, the CVE-2022-39944 vulnerability found in Apache Linkis <=1.2. with MySQL Connector/J poses a significant risk of remote code execution when exploited. Users should update their systems to Apache Linkis 1.3. and consider employing blacklisting techniques to further minimize possible attack vectors.

References

1. CVE-2022-39944 on NVD
2. Apache Linkis Official Website
3. Apache Linkis 1.3. Upgrade Instructions
4. MySQL Connector/J Official Website

Timeline

Published on: 10/26/2022 16:15:00 UTC
Last modified on: 10/28/2022 17:40:00 UTC