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class NativeCode {
  public native void loadLib();

  static {
    try {
      System.loadLibrary("/com/foo/MyLib.so");
    }catch(UnsatisfiedLinkError e) { e.getMessage(); }
  }    
}

class Untrusted {
  public static void untrustedCode() {
    new NativeCode().loadLib();
  }
}

Sometimes, a call to System.loadLibrary is embedded in a doPrivileged block, as shown below. An unprivileged caller can maliciously invoke this piece of code.

AccessController.doPrivileged(new PrivilegedAction() {
  public Object run() { 
    System.loadLibrary("awt");
    return null; 
  }
});

Noncompliant Code Example

The single argument Class.forname method is another example of an API that uses its immediate caller's class loader to load a desired class. Untrusted code can indirectly abuse this API.

Class c = Class.forName(className);

Compliant Solution

Ensure that untrusted code cannot invoke the affected APIs directly or indirectly (that is, via a call to an invoking method). Do not operate on tainted inputs and make sure that internal objects are not returned to untrusted code.

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