How to Protect the Password Field in Mongoose/MongoDB.

When working with Mongoose and MongoDB, it is important to protect sensitive data such as passwords. One common concern is ensuring that the password field is not returned in query results, especially when populating collections.

In this article, we’ll explore How to protect the password field in Mongoose/MongoDB so it won’t return in a query when I populate collections by understanding various methods along with the implementation and so on.

Understanding the Risk

• The population technique of Mongoose which is being used for fetching the related documents from the reference collections and should be used with care while deciding the fields in the query results.
• Because passwords use a field schema and they can be exposed if we don’t handle them properly and it is a significant danger to the security of our site.

Methods to Protect Password Fields

1. Exclude Password Field from Query Results:

The easiest way is to build a design that disallows responses with the password field from local database queries. This can be done by setting the select option to “password” when obtaining Mongoose schema.

const userSchema = new Schema({
    username: String,
    password: { type: String, select: false },
    // Other fields...
});

Explanation: In this method, we define the schema for the user with the select option set to false for the password field. This ensures that the password field is excluded from query results.

2. Use Virtuals for Password Fields

Another approach is to use Mongoose virtuals to compute a virtual field for the password which ensuring that it never stored in the database or returned in queries.

userSchema.virtual('password').get(function() {
    return undefined;
});

Explanation: This way, even if the password field is populated, it will always return undefined.

3. Apply Middleware to Filter Password Field

Mongoose middleware, such as pre or post hooks, can be used to intercept queries and filter out the password field before the results are returned.

userSchema.pre('find', function(next) {
    this.select('-password');
    next();
});

Explanation: By applying middleware, we can ensure that the password field is excluded from all queries by default.

4. Encrypted Password Storage:

Instead of storing passwords as plain text, you can encrypt them before saving them to the database. This ensures that even if the password field is inadvertently included in query results, the actual passwords remain encrypted and unreadable.

const bcrypt = require('bcrypt');

// Middleware to hash the password before saving the user
userSchema.pre('save', async function(next) {
    // Check if the password has been modified, if not, skip hashing
    if (!this.isModified('password')) {
        return next();
    }

    try {
        // Generate a salt with a complexity factor of 10
        const salt = await bcrypt.genSalt(10);
        // Hash the password with the generated salt
        const hashedPassword = await bcrypt.hash(this.password, salt);
        // Replace the plain text password with the hashed password
        this.password = hashedPassword;
        next();
    } catch (error) {
        // Pass any error to the next middleware
        next(error);
    }
});

Explanation: This technique involves using a hashing algorithm such as bcrypt to encrypt the password and then store its encrypted version in the database. During the request of documents, an encrypted password will be sent back which will ensure the confidentiality by the fact that encryption is one-way. Through this practice we make certain that passwords are safe and not a possible outcome while populating collections with queries.

Conclusion

Overall, Privacy is an important factor in data security, and passwords are one of the most common sensitive data in use in MongoDB and Mongoose applications. These best practices comprise of excluding password fields from query results, use of virtuals, applying middleware and encrypting passwords that when applying them developers reduce the risk of unintentional leakage when populating collections. Therefore, the model should be implemented for ensuring the data integrity and application security.