MongoDB: How to temporarily disable a user

Introduction

In distributed databases like MongoDB, managing user access is critical to secure data and resources. There are instances where a user account needs to be temporarily disabled without deleting the account permanently. This guides you through the process of disabling a MongoDB user temporarily with comprehensive code examples covering basic to advanced scenarios.

Understanding MongoDB User Management

Before proceeding to disable a user, it’s essential to understand MongoDB’s user management. Users in MongoDB are stored in the system.users collection of the admin database. Each user has roles that grant them various access rights to databases and operations.

Basic User Information Query

The first step is to retrieve information about the user you want to disable:

use admin
db.getCollection("system.users").find({user: "exampleUser"})

This command will return the user document from the system.users collection.

Simple User Disabling

To disable a user account temporarily, you remove the user’s roles. This example shows you how:

use admin
db.updateUser("exampleUser", {roles: []})

This removes all roles from the user exampleUser, rendering the account inactive without any access rights.

Confirming User Disablement

Confirm that the user’s roles have been removed:

use admin
db.getUser("exampleUser")

This should now show that the exampleUser has no roles assigned.

Advanced User Disabling Scenarios

For advanced use cases, you might need to disable multiple users or all users associated with a specific role. Here’s how you can achieve that:

Disabling Multiple Users

Disabling multiple users at once can be done with a script. Here’s an example using the MongoDB shell:

use admin
var users = ["user1", "user2", "user3"]
users.forEach(function(user) {
  db.updateUser(user, {roles: []})
})

This script will go through the list of users provided in the array and disable each of them by setting their roles to an empty array.

Disabling Users by Role

If you want to disable all users belonging to a specific role, you can use the following script:

use admin
var roleName = "readWrite"
db.getCollection("system.users").find({"roles.role": roleName}).forEach(function(user) {
  db.updateUser(user.user, {roles: []})
})

Re-enabling a User

To re-enable a user, you need to assign their roles back. Store the user’s roles before disabling them so that you can reassign the correct roles later:

use admin
var userRoles = db.getUser("exampleUser").roles
db.updateUser("exampleUser", {roles: []})
// When re-enabling
use admin
db.updateUser("exampleUser", {roles: userRoles})

By restoring the previously stored roles back to the user, you effectively re-enable their account.

Auditing and Security Considerations

When disabling and re-enabling users, always consider auditing the changes and ensure adherence to security best practices. It’s important to log who disabled the user and when.

Audit log example:

// Enable auditing in MongoDB to track user-management operations
db.adminCommand({
  setParameter: 1,
  auditAuthorizationSuccess: true
})

Proper auditing helps in maintaining a secure environment and assists in compliance with data protection regulations.

Script Automation for User Disablement

Automating the process of temporarily disabling a user in MongoDB can be done through scripting. I’ll provide an example using a simple script. This script will connect to MongoDB, disable a specified user, and can be easily modified or extended for other user management tasks.

Assuming you have a MongoDB environment set up and the mongo shell available, here’s how you can create a script for this purpose:

Step 1: Create the Script

Create a new file named disableUser.js (you can choose any name you like). This script will be run using the MongoDB shell.

// disableUser.js

// Function to disable a user
function disableUser(username, dbName) {
    // Connect to the admin database
    var adminDb = db.getSiblingDB('admin');

    // Update the user to disable it
    adminDb.updateUser(username, { $set: { disabled: true } });

    // Print the status
    print("User '" + username + "' has been disabled.");
}

// The database where the user exists
var dbName = 'yourDatabaseName'; // Replace with your database name

// The username of the user to disable
var username = 'yourUsername'; // Replace with the username to disable

// Call the function to disable the user
disableUser(username, dbName);

Step 2: Run the Script

Run the script using the mongo shell command. Make sure to replace yourDatabaseName and yourUsername with the actual database name and username.

mongo yourDatabaseName disableUser.js

Step 3: Automating the Script

You can automate this script using a task scheduler or cron job, depending on your operating system. For example, on a Linux system, you can set up a cron job to run this script at specific intervals.

#!/bin/bash
# Create a shell script wrapper for the MongoDB script
echo '#!/bin/bash
MONGO_PATH=/usr/bin/mongo
SCRIPT_PATH=/path/to/disableUser.js
DB_NAME=yourDatabaseName
$MONGO_PATH $DB_NAME $SCRIPT_PATH' > runMongoScript.sh

# Make the script executable
chmod +x runMongoScript.sh

# Add a cron job to run the script every day at 1 AM and log output
(crontab -l 2>/dev/null; echo "0 1 * * * /path/to/runMongoScript.sh >> /path/to/logfile.log 2>&1") | crontab -

Make sure to replace /usr/bin/mongo, /path/to/disableUser.js, yourDatabaseName, /path/to/runMongoScript.sh, and /path/to/logfile.log with your actual paths and database name.

Note:

• MongoDB doesn’t have a built-in disabled property for users, so this script uses a custom field. You’ll need to modify your authentication logic to recognize and enforce this disabled field.
• Ensure you have the necessary permissions to run user management commands in MongoDB.
• Always test scripts in a safe environment before using them in production.
• This script is a basic example for educational purposes. In a real-world scenario, you might want to include error handling and logging.

Conclusion

Disabling a MongoDB user temporarily is straightforward with the built-in updateUser command. This method ensures that user accounts remain intact while their access is restricted. User management requires careful consideration, documentation, and preferably, automation to streamline processes and comply with best practices.