What is Improper Neutralization (CWE-141)?

TL;DR: Improper Neutralization of Parameter/Argument Delimiters (CWE-141) occurs when a product receives input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements. This vulnerability can allow attackers to inject malicious code and compromise sensitive data.

What is Improper Neutralization of Parameter/Argument Delimiters?

Improper Neutralization of Parameter/Argument Delimiters (CWE-141) is a type of vulnerability that occurs when a product receives input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could be interpreted as parameter or argument delimiters. This can allow attackers to inject malicious code into the application and compromise sensitive data.

As defined by the MITRE Corporation under CWE-141, this vulnerability is classified as a high-severity issue that requires prompt attention.

Quick Summary

Improper Neutralization of Parameter/Argument Delimiters (CWE-141) is a type of vulnerability that can allow attackers to inject malicious code into an application. This can lead to other security vulnerabilities and potentially compromise sensitive data. To prevent CWE-141, developers should use input validation, sanitization, and escaping techniques to ensure that only valid and expected input is processed by the system.

Jump to: Quick Summary · Improper Neutralization of Parameter/Argument Delimiters Overview · How Improper Neutralization of Parameter/Argument Delimiters Works · Business Impact of Improper Neutralization of Parameter/Argument Delimiters · Improper Neutralization of Parameter/Argument Delimiters Attack Scenario · How to Detect Improper Neutralization of Parameter/Argument Delimiters · How to Fix Improper Neutralization of Parameter/Argument Delimiters · Framework-Specific Fixes for Improper Neutralization of Parameter/Argument Delimiters · How to Ask AI to Check Your Code for Improper Neutralization of Parameter/Argument Delimiters · Improper Neutralization of Parameter/Argument Delimiters Best Practices Checklist · Improper Neutralization of Parameter/Argument Delimiters FAQ · Vulnerabilities Related to Improper Neutralization of Parameter/Argument Delimiters · References · Scan Your Own Site

Improper Neutralization of Parameter/Argument Delimiters Overview

Improper Neutralization of Parameter/Argument Delimiters (CWE-141) is a type of vulnerability that occurs when a product receives input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements. This can allow attackers to inject malicious code into the application and compromise sensitive data.

What: Improper Neutralization of Parameter/Argument Delimiters (CWE-141) is a type of vulnerability that occurs when a product receives input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements.

Why it matters: CWE-141 can allow attackers to inject malicious code into the application and compromise sensitive data. It is essential to address this vulnerability promptly to prevent further attacks.

Where it occurs: CWE-141 can occur in any type of application that receives user-inputted data, including web applications, mobile applications, and APIs.

Who is affected: Any organization that uses a product with CWE-141 vulnerabilities may be affected. This includes organizations that use web applications, mobile applications, or APIs that receive user-inputted data.

Who is NOT affected: Organizations that do not use products with CWE-141 vulnerabilities are not affected.

How Improper Neutralization of Parameter/Argument Delimiters Works

Improper Neutralization of Parameter/Argument Delimiters (CWE-141) occurs when a product receives input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements. This can allow attackers to inject malicious code into the application and compromise sensitive data.

Root Cause

The root cause of CWE-141 is that the product does not properly neutralize or escape special elements in user-inputted data. This allows attackers to inject malicious code into the application.

Attack Flow

1. An attacker sends a request with malicious input to the vulnerable application.
2. The application receives the request and processes it without properly neutralizing or escaping special elements.
3. The malicious code is injected into the application, allowing the attacker to compromise sensitive data.

Prerequisites to Exploit

For CWE-141 to be exploitable, the following prerequisites must be true:

• The product must receive user-inputted data from an upstream component.
• The product must not properly neutralize or escape special elements in the input data.
• The attacker must have access to the vulnerable application and be able to send requests with malicious input.

Vulnerable Code

import os

def process_input(input_data):
    # Do not sanitize or escape special elements
    command = input_data
    os.system(command)

This code is vulnerable because it does not properly neutralize or escape special elements in the input data. An attacker can inject malicious code into the application by sending a request with malicious input.

Secure Code

import os

def process_input(input_data):
    # Sanitize and escape special elements
    command = "echo {}".format(input_data)
    os.system(command)

This code is secure because it properly sanitizes and escapes special elements in the input data. An attacker cannot inject malicious code into the application by sending a request with malicious input.

Business Impact of Improper Neutralization of Parameter/Argument Delimiters

Improper Neutralization of Parameter/Argument Delimiters (CWE-141) can have significant business impacts, including:

• Data breaches: CWE-141 can allow attackers to compromise sensitive data and steal confidential information.
• Financial losses: CWE-141 can result in financial losses due to data breaches, system downtime, and other related costs.
• Reputation damage: CWE-141 can damage an organization’s reputation if it is publicly disclosed that the organization has a vulnerability that was exploited by an attacker.

Improper Neutralization of Parameter/Argument Delimiters Attack Scenario

Here is a step-by-step walkthrough of how an attacker might exploit CWE-141:

1. An attacker sends a request with malicious input to the vulnerable application.
2. The application receives the request and processes it without properly neutralizing or escaping special elements.
3. The malicious code is injected into the application, allowing the attacker to compromise sensitive data.

How to Detect Improper Neutralization of Parameter/Argument Delimiters

To detect CWE-141, use a combination of manual testing and automated scanning tools. Manual testing involves reviewing the application’s code and input validation mechanisms for potential vulnerabilities. Automated scanning tools can help identify potential vulnerabilities by analyzing the application’s input data.

Manual Testing

• Review the application’s code and input validation mechanisms for potential vulnerabilities.
• Test the application with malicious input to see if it is vulnerable to CWE-141.

Automated Scanners (SAST / DAST)

• Use automated scanning tools to analyze the application’s input data for potential vulnerabilities.
• These tools can help identify potential CWE-141 vulnerabilities by analyzing the application’s code and input validation mechanisms.

PenScan Detection

PenScan’s scanner engines can detect CWE-141 vulnerabilities and provide recommendations for remediation.

False Positive Guidance

To avoid false positives, review the results of automated scanning tools carefully. If a vulnerability is detected, verify that it is indeed a CWE-141 vulnerability by reviewing the application’s code and input validation mechanisms.

How to Fix Improper Neutralization of Parameter/Argument Delimiters

To fix CWE-141 vulnerabilities, use input validation, sanitization, and escaping techniques to ensure that only valid and expected input is processed by the system. Additionally, developers can use denylists and allowlists to restrict the types of data that can be entered into the application.

Framework-Specific Fixes for Improper Neutralization of Parameter/Argument Delimiters

Here are some framework-specific fixes for CWE-141:

Java

import java.util.regex.Pattern;

public class InputValidator {
    public static boolean validateInput(String input) {
        // Use regular expressions to sanitize and escape special elements
        Pattern pattern = Pattern.compile("[^a-zA-Z0-9]");
        if (pattern.matcher(input).find()) {
            return false;
        }
        return true;
    }
}

Node.js

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

app.use(express.urlencoded({ extended: true }));

function validateInput(req, res, next) {
    // Use regular expressions to sanitize and escape special elements
    const input = req.body.input;
    const pattern = /^[a-zA-Z0-9]+$/;
    if (!pattern.test(input)) {
        return res.status(400).send('Invalid input');
    }
    next();
}

Python/Django

from django.core.exceptions import ValidationError

def validate_input(input_data):
    # Use regular expressions to sanitize and escape special elements
    pattern = r'^[a-zA-Z0-9]+$'
    if not re.match(pattern, input_data):
        raise ValidationError('Invalid input')

PHP

function validateInput($input) {
    // Use regular expressions to sanitize and escape special elements
    $pattern = '/[^a-zA-Z0-9]/';
    if (preg_match($pattern, $input)) {
        return false;
    }
    return true;
}

How to Ask AI to Check Your Code for Improper Neutralization of Parameter/Argument Delimiters

To ask an AI coding assistant to check your code for CWE-141 vulnerabilities, use the following prompt:

“Review the following [language] code block for potential CWE-141 Improper Neutralization of Parameter/Argument Delimiters vulnerabilities and rewrite it using input validation, sanitization, and escaping techniques: [paste code here].”

Improper Neutralization of Parameter/Argument Delimiters Best Practices Checklist

Here are some best practices to follow when developing applications that receive user-inputted data:

✅ Use input validation, sanitization, and escaping techniques to ensure that only valid and expected input is processed by the system. ✅ Use denylists and allowlists to restrict the types of data that can be entered into the application. ✅ Regularly review and update your application’s code and input validation mechanisms to prevent CWE-141 vulnerabilities.

Improper Neutralization of Parameter/Argument Delimiters FAQ

How do I prevent CWE-141?

To prevent CWE-141, developers should anticipate that parameter/argument delimiters will be injected/removed/manipulated in the input vectors of their product. Use an appropriate combination of denylists and allowlists to ensure only valid, expected, and appropriate input is processed by the system.

What are some common examples of CWE-141 vulnerabilities?

CWE-141 can occur when a web application receives user-inputted data that contains special characters, such as semicolons or parentheses. If these characters are not properly sanitized or escaped, they can be used to inject malicious code into the application.

Can CWE-141 lead to other security vulnerabilities?

Yes, CWE-141 can lead to other security vulnerabilities if left unaddressed. It can allow attackers to inject malicious code, which can then be used to exploit other vulnerabilities in the system.

How do I detect CWE-141 in my application?

To detect CWE-141, use a combination of manual testing and automated scanning tools. Manual testing involves reviewing the application’s code and input validation mechanisms for potential vulnerabilities. Automated scanning tools can help identify potential vulnerabilities by analyzing the application’s input data.

What are some common mitigation strategies for CWE-141?

Some common mitigation strategies for CWE-141 include using input validation, sanitization, and escaping techniques to ensure that only valid and expected input is processed by the system. Additionally, developers can use denylists and allowlists to restrict the types of data that can be entered into the application.

Can CWE-141 occur in any type of application?

Yes, CWE-141 can occur in any type of application that receives user-inputted data, including web applications, mobile applications, and APIs.

How do I fix CWE-141 vulnerabilities in my application?

To fix CWE-141 vulnerabilities, developers should review the application’s code and input validation mechanisms to identify potential vulnerabilities. They can then use a combination of manual testing and automated scanning tools to verify that the vulnerabilities have been addressed.

Vulnerabilities Related to Improper Neutralization of Parameter/Argument Delimiters

Here are some related vulnerabilities:

References

• MITRE CWE-141
• 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 CWE-141 and other risks before an attacker does.