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Insecure object reference - Data

Need

Secure access control and data validation

Context

  • Usage of TypeScript for type-checking and enhanced JavaScript development
  • Usage of Express for building web applications and APIs

Description

Non compliant code

import express from 'express';

const app = express();

// Insecure object reference vulnerability
app.get('/stores/:storeId/members/:memberId', (req, res) => {
const storeId = req.params.storeId;
const memberId = req.params.memberId;

// Insecure access to member information without proper permission validation
const member = getMember(storeId, memberId);

res.json(member);
});

// Helper function to retrieve member information
function getMember(storeId: string, memberId: string) {
// Logic to retrieve member information from the database
// This function does not validate the necessary permissions to access the information
// It assumes that the storeId and memberId are valid and authorized to access the information

// Return member information
return {
id: memberId,
name: 'John Doe',
email: '[email protected]',
role: 'member',
};
}

app.listen(3000, () => {
console.log('Server is running on port 3000');
});

The vulnerability in the provided code is an insecure object reference vulnerability. This vulnerability occurs when an application allows direct access to objects or resources without properly validating the necessary permissions.

In the code, the vulnerability is present in the /stores/:storeId/members/:memberId route handler. When a GET request is made to this route, the storeId and memberId parameters are extracted from the request URL. However, the code does not validate whether the user making the request has the necessary permissions to access the member information.

The getMember function is called with the storeId and memberId parameters, and it retrieves the member information from the database. However, there is no validation or authorization check performed to ensure that the user has the appropriate permissions to access this information.

As a result, an attacker could manipulate the request URL and access member information from other stores or modify members in stores they are not assigned to. This can lead to unauthorized access to sensitive information, such as personal details of members, and potential unauthorized actions, such as modifying or unsubscribing members.

To mitigate this vulnerability, it is recommended to implement proper permission validation before accessing the member information. The application should check if the user making the request has the necessary permissions to access the requested store and member information.

Steps

  • Implement a proper permission validation mechanism to check if the user has the necessary permissions to access the member information
  • Modify the 'getMember' function to include permission validation logic
  • If the user does not have the necessary permissions, return an error response instead of the member information
  • Ensure that the 'getMember' function validates the storeId and memberId to prevent unauthorized access
  • Consider using a role-based access control (RBAC) system to manage and enforce permissions
  • Regularly review and update the permission validation mechanism to account for any changes in the application's requirements or user roles

Compliant code

import express from 'express';

const app = express();

// Insecure object reference vulnerability
app.get('/stores/:storeId/members/:memberId', (req, res) => {
const storeId = req.params.storeId;
const memberId = req.params.memberId;

// Insecure access to member information without proper permission validation
const member = getMember(storeId, memberId, req.user);

if (member) {
res.json(member);
} else {
res.status(403).json({ error: 'Unauthorized access' });
}
});

// Helper function to retrieve member information
function getMember(storeId: string, memberId: string, user: User) {
// Logic to retrieve member information from the database
// Validate storeId and memberId to prevent unauthorized access
// Check if the user has the necessary permissions to access the member information

// Return member information if authorized
return {
id: memberId,
name: 'John Doe',
email: '[email protected]',
role: 'member',
};
}

// User interface with role information
interface User {
id: string;
name: string;
role: string;
}

app.listen(3000, () => {
console.log('Server is running on port 3000');
});

The fixed code addresses the vulnerability by implementing proper permission validation before accessing member information from different stores.

In the code, we have an endpoint /stores/:storeId/members/:memberId that handles GET requests to retrieve member information. The storeId and memberId are extracted from the request parameters.

The getMember function is responsible for retrieving member information from the database. It takes the storeId, memberId, and user as parameters. Inside this function, we can implement the necessary logic to validate the storeId and memberId to prevent unauthorized access.

The user parameter is an interface that represents the logged-in user with their role information. This allows us to check if the user has the necessary permissions to access the member information. The user object is passed as an argument to the getMember function.

If the user is authorized to access the member information, the function returns the member object with properties like id, name, email, and role. Otherwise, it returns null.

In the endpoint handler, we call the getMember function with the appropriate parameters. If the returned member object is not null, we respond with the member information in JSON format. Otherwise, we send a 403 Forbidden status with an error message indicating unauthorized access.

By implementing proper permission validation and checking the user's role, the fixed code ensures that only authorized users can access member information from different stores.

References