Java

JAVA.CLASS.SER.ND : Serialization Not Disabled (Java)

Summary

Serialization for a class has not been explicitly disabled by defining a writeObject() method that always throws an exception.

Properties

Class Name Serialization Not Disabled (Java)
Significance reliability
Mnemonic JAVA.CLASS.SER.ND
Categories
CWE CWE:499 Serializable Class Containing Sensitive Data
  CWE:502 Deserialization of Untrusted Data
CERT-Java CERT-Java:SER01-J Do not deviate from the proper signatures of serialization methods
  CERT-Java:SER03-J Do not serialize unencrypted sensitive data
  CERT-Java:SER06-J Make defensive copies of private mutable components during deserialization
  CERT-Java:SER07-J Do not use the default serialized form for classes with implementation-defined invariants
  CERT-Java:SER12-J Prevent deserialization of untrusted data
Availability Available for Java only.
Enabling Checks for this warning class are disabled by default. To enable them, add the following WARNING_FILTER rule to the project configuration file. 
WARNING_FILTER += allow class="Serialization Not Disabled (Java)"

Example

In the following code excerpt, class MyWindow is serializable (because it extends serializable class JFrame).

However, the programmer has annotated the class with @SuppressWarnings("serial"), suppressing any compiler warnings about the missing serialVersionUID field. CodeSonar observes this suppression and reasons that the programmer does not intend the class to be serialized. However, serialization has not been explicitly disabled. 

// MyWindow.java
import javax.swing.JFrame;

@SuppressWarnings("serial")
public class MyWindow extends JFrame {  // "Serialization Not Disabled" warning issued here 
  private final int secret;

  public MyWindow(int secret) {
      this.secret = secret;
  }
}

In this example, the programmer should explicitly prevent serialization of class MyWindow, as follows. 

// MyWindow.java, after modification
import java.io.ObjectOutputStream;
import javax.swing.JFrame;

@SuppressWarnings("serial")
public class MyWindow extends JFrame {
  private final int secret;

  public MyWindow(int secret) {
      this.secret = secret;
  }

  private void writeObject(ObjectOutputStream stream) {
      throw new RuntimeException("Serialization is not allowed");
  }
}

Relevant Configuration File Parameters

The following configuration file parameters affect checks for this warning class.