CWE-651: Exposure of WSDL File Containing Sensitive Information

What is Exposure of WSDL File Containing Sensitive Information?

• Overview: Exposure of WSDL File Containing Sensitive Information (CWE-651) occurs when a Web Service Definition Language (WSDL) file, which provides details on web services and how to interact with them, is accessible to unauthorized users or contains sensitive information that should not be publicly available.

• Exploitation Methods:

• Attackers can exploit this vulnerability by accessing the WSDL file to gain insights into the web service's functionality and endpoints.
• Common attack patterns include using the information in the WSDL to identify and target non-public methods or deprecated services.

• Security Impact:

• Direct consequences of successful exploitation include unauthorized access to web services and potential exposure of sensitive data.
• Potential cascading effects may involve further information disclosure and increased attack surface for other vulnerabilities.
• Business impact could include reputational damage, legal liabilities, and financial losses due to data breaches.

• Prevention Guidelines:

• Specific code-level fixes include ensuring that only necessary information is included in the WSDL and removing details about non-public or deprecated methods.
• Security best practices involve restricting access to WSDL files to authorized users only and regularly reviewing and updating WSDL files to remove outdated information.
• Recommended tools and frameworks include using security gateways or firewalls to control access and employing automated tools to scan WSDL files for sensitive information.

Corgea can automatically detect and fix Exposure of WSDL File Containing Sensitive Information in your codebase. [Try Corgea free today](https://corgea.app).

Technical Details

Likelihood of Exploit: Not specified

Affected Languages: Not Language-Specific

Affected Technologies: Web Server

Vulnerable Code Example

JavaScript Example

// Node.js Express server serving a WSDL file directly
const express = require('express');
const fs = require('fs');
const app = express();

app.get('/wsdl', (req, res) => {
    // Exposing WSDL file publicly without any restriction
    fs.readFile('service.wsdl', 'utf8', (err, data) => {
        if (err) {
            res.status(500).send('Error reading WSDL file');
        } else {
            // The WSDL file is served without any authentication or encryption
            res.type('application/xml').send(data);
        }
    });
});

app.listen(3000, () => {
    console.log('Server running on http://localhost:3000');
});

Explanation

In this vulnerable example, the WSDL file is exposed publicly without any form of access control or encryption. This means anyone who can access the URL can download the WSDL file, which may contain sensitive information about the web service's operations and endpoints.

How to fix Exposure of WSDL File Containing Sensitive Information?

To protect sensitive information in WSDL files, follow these best practices:

1. Restrict Access: Implement authentication and authorization to ensure only authorized users or systems can access the WSDL file.

2. Environment Isolation: Avoid exposing WSDL files in production environments unless necessary. Use environment variables or configuration files to control access.

3. Logging and Monitoring: Implement logging and monitoring to detect unauthorized access attempts to WSDL files.

4. Use HTTPS: Always serve WSDL files over HTTPS to prevent interception and tampering of data in transit.

Fixed Code Example

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

// Middleware to check for authentication
function isAuthenticated(req, res, next) {
    // Implement your authentication logic here
    if (req.isAuthenticated && req.isAuthenticated()) {
        return next();
    }
    res.status(403).send('Forbidden');
}

// Secure WSDL endpoint with authentication
app.get('/wsdl', isAuthenticated, (req, res) => {
    fs.readFile('service.wsdl', 'utf8', (err, data) => {
        if (err) {
            res.status(500).send('Error reading WSDL file');
        } else {
            // The WSDL file is now protected by authentication
            res.type('application/xml').send(data);
        }
    });
});

app.listen(3000, () => {
    console.log('Server running on https://localhost:3000'); // Ensure HTTPS is used in production
});

Explanation

In the fixed code example, an authentication middleware isAuthenticated is added to the /wsdl endpoint, ensuring that only authorized users can access the WSDL file. Additionally, it is advised to run the server over HTTPS in production to protect data in transit. This example illustrates how to secure sensitive WSDL files effectively by implementing authentication and encryption.