What is Struts: Duplicate Validation Forms (CWE-102)?

TL;DR: Struts: Duplicate Validation Forms (CWE-102) is a vulnerability that occurs when multiple validation forms with the same name are used in a web application. It can cause unexpected state and potential integrity issues.

What is Struts: Duplicate Validation Forms?

Struts: Duplicate Validation Forms (CWE-102) is a type of vulnerability that occurs when a web application uses multiple validation forms with the same name, causing unexpected behavior in the Struts Validator. As defined by the MITRE Corporation under CWE-102, and classified by the OWASP Foundation as not directly mapped to any category, this vulnerability can lead to unexpected state and potential integrity issues.

Quick Summary

Struts: Duplicate Validation Forms (CWE-102) is a type of vulnerability that occurs when multiple validation forms with the same name are used in a web application. This can cause unexpected state and potential integrity issues. It’s essential to detect and prevent this vulnerability to ensure the security of your web application.

Jump to: Quick Summary · Struts: Duplicate Validation Forms Overview · How Struts: Duplicate Validation Forms Works · Business Impact of Struts: Duplicate Validation Forms · Struts: Duplicate Validation Forms Attack Scenario · How to Detect Struts: Duplicate Validation Forms · How to Fix Struts: Duplicate Validation Forms · Framework-Specific Fixes for Struts: Duplicate Validation Forms · How to Ask AI to Check Your Code for Struts: Duplicate Validation Forms · Struts: Duplicate Validation Forms Best Practices Checklist · Struts: Duplicate Validation Forms FAQ · Vulnerabilities Related to Struts: Duplicate Validation Forms · References · Scan Your Own Site

Struts: Duplicate Validation Forms Overview

What: Struts: Duplicate Validation Forms (CWE-102) is a type of vulnerability that occurs when multiple validation forms with the same name are used in a web application.

Why it matters: This vulnerability can lead to unexpected state and potential integrity issues.

Where it occurs: This vulnerability typically occurs in web applications that use Struts for validation.

Who is affected: Web developers, security professionals, and users of web applications that use Struts for validation.

Who is NOT affected: Users of web applications that do not use Struts for validation.

How Struts: Duplicate Validation Forms Works

Root Cause

The root cause of this vulnerability is the use of multiple validation forms with the same name in a web application.

Attack Flow

1. The attacker sends a request to the web application with a duplicate form name.
2. The web application processes the request and uses the duplicate form name for validation.
3. The Struts Validator causes unexpected behavior, leading to potential integrity issues.

Prerequisites to Exploit

• The web application must use Struts for validation.
• The attacker must be able to send a request with a duplicate form name.

Vulnerable Code

public class ValidationForm {
  public void validate(String formName) {
    // Use the formName for validation
  }
}

The vulnerable code uses the formName parameter without checking if it is unique. This allows an attacker to send a request with a duplicate form name, causing unexpected behavior in the Struts Validator.

Secure Code

public class ValidationForm {
  public void validate(String formName) {
    // Check if the formName is unique before using it for validation
    if (formNames.contains(formName)) {
      throw new Exception("Duplicate form name");
    }
  }
}

The secure code checks if the formName parameter is unique before using it for validation. This prevents unexpected behavior in the Struts Validator.

Business Impact of Struts: Duplicate Validation Forms

Confidentiality: There is no impact on confidentiality, as this vulnerability does not involve sensitive data.

Integrity: The potential integrity issues caused by this vulnerability can lead to unauthorized changes to web application data.

Availability: There is no impact on availability, as this vulnerability does not cause the web application to become unavailable.

The business consequences of Struts: Duplicate Validation Forms include:

• Potential integrity issues
• Unauthorized changes to web application data

Struts: Duplicate Validation Forms Attack Scenario

1. The attacker sends a request to the web application with a duplicate form name.
2. The web application processes the request and uses the duplicate form name for validation.
3. The Struts Validator causes unexpected behavior, leading to potential integrity issues.

How to Detect Struts: Duplicate Validation Forms

Manual Testing

• Review xml configuration files for duplicate form names
• Test the web application with a duplicate form name

Automated Scanners (SAST / DAST)

Automated scanners can detect this vulnerability by analyzing the web application’s code and configuration.

PenScan Detection

PenScan’s scanner engines actively test for this issue.

False Positive Guidance

To avoid false positives, ensure that the web application uses unique form names and review xml configuration files regularly.

How to Fix Struts: Duplicate Validation Forms

• Use the DTD or schema validation to check for duplicate form names
• Manually review xml configuration files
• Ensure that the web application uses unique form names

Framework-Specific Fixes for Struts: Duplicate Validation Forms

Java

public class ValidationForm {
  public void validate(String formName) {
    // Check if the formName is unique before using it for validation
    if (formNames.contains(formName)) {
      throw new Exception("Duplicate form name");
    }
  }
}

Node.js

const express = require('express');
const app = express();

app.post('/validate', (req, res) => {
  const formName = req.body.formName;
  // Check if the formName is unique before using it for validation
  if (formNames.includes(formName)) {
    return res.status(400).send({ error: 'Duplicate form name' });
  }
});

Python/Django

from django.http import HttpResponse

def validate(request):
  form_name = request.POST.get('form_name')
  # Check if the form_name is unique before using it for validation
  if form_names.contains(form_name):
    return HttpResponse('Duplicate form name', status=400)

PHP

<?php
public function validate($formName) {
  // Check if the formName is unique before using it for validation
  if (in_array($formName, $formNames)) {
    throw new Exception('Duplicate form name');
  }
}
?>

How to Ask AI to Check Your Code for Struts: Duplicate Validation Forms

You can use AI to review your code and identify potential vulnerabilities related to Struts: Duplicate Validation Forms. Here’s a copy-pasteable prompt you can use with an AI coding assistant:

Review the following Java code block for potential CWE-102 Struts: Duplicate Validation Forms vulnerabilities and rewrite it using primary fix technique: ensuring unique form names.

public class ValidationForm {
  public void validate(String formName) {
    // Use the formName for validation
  }
}

Struts: Duplicate Validation Forms Best Practices Checklist

✅ Ensure that the web application uses unique form names. ✅ Review xml configuration files regularly to detect duplicate form names.

Struts: Duplicate Validation Forms FAQ

How does Struts: Duplicate Validation Forms occur?

Struts: Duplicate Validation Forms occurs when a web application uses multiple validation forms with the same name, causing unexpected behavior in the Struts Validator.

What are the consequences of Struts: Duplicate Validation Forms?

The consequences of Struts: Duplicate Validation Forms include unexpected state and potential integrity issues.

How can I detect Struts: Duplicate Validation Forms?

You can detect Struts: Duplicate Validation Forms through manual testing, automated scanners, or PenScan detection.

How do I fix Struts: Duplicate Validation Forms?

To fix Struts: Duplicate Validation Forms, you should use the DTD or schema validation to check for duplicate form names and manually review xml configuration files.

What are some best practices for preventing Struts: Duplicate Validation Forms?

Some best practices for preventing Struts: Duplicate Validation Forms include using unique form names and reviewing xml configuration files regularly.

Can AI help me detect and prevent Struts: Duplicate Validation Forms?

Yes, you can use AI to review your code and identify potential vulnerabilities related to Struts: Duplicate Validation Forms.

What are some common mistakes that lead to Struts: Duplicate Validation Forms?

Some common mistakes that lead to Struts: Duplicate Validation Forms include using duplicate form names and not reviewing xml configuration files regularly.

Vulnerabilities Related to Struts: Duplicate Validation Forms

References

• MITRE CWE-102
• NVD

Scan Your Own Site

Manual code review catches what you know to look for. An automated scan catches what you didn’t. Scan your own website using PenScan to find Struts: Duplicate Validation Forms and other risks before an attacker does.