Broken Access Control in Laravel with Mongodb

Broken Access Control (BOLA/IDOR) in a Laravel application using MongoDB typically arises when application-level permissions are enforced solely on data retrieved via Laravel models or queries, without guaranteeing that each request operates only on resources the authenticated user is permitted to access. Because MongoDB is a schemaless, document-oriented store, it does not enforce row-level or field-level permissions automatically; it is the application that must encode these rules consistently in every query.

In Laravel, developers often rely on route model binding to fetch a MongoDB document by ID (e.g., using a custom MongoDB Eloquent-like model or a repository). If the binding resolves a document without checking ownership or tenant context, an attacker can modify the identifier in the request (IDOR) and access other users’ data. For example, a route like /api/users/{user} that binds directly to a MongoDB document by _id without verifying that the authenticated user owns or is allowed to view that document enables BOLA/IDOR.

Moreover, MongoDB’s flexible schema can lead to inconsistent field naming or missing authorization checks across endpoints. If authorization logic is implemented in only a subset of controllers or services, an attacker can pivot to less-guarded endpoints. Inconsistent use of middleware (for example, applying auth middleware to some routes but not others) compounds the risk. The lack of a fixed schema also means developers might inadvertently expose sensitive fields (such as roles, permissions, or PII) in query results when projections are not explicitly restricted.

Another common pattern is using complex query filters that reference user context (e.g., user_id or tenant_id) stored inside documents. If these filters are constructed dynamically without strict validation, an attacker may inject or manipulate query operators to bypass intended restrictions. For instance, omitting a tenant filter or using an unchecked $where JavaScript expression can expose cross-tenant data.

Finally, because OpenAPI/Swagger spec analysis (with full $ref resolution) can reveal which endpoints expose MongoDB identifiers without corresponding authorization checks, scanning helps identify these gaps. The scanner tests unauthenticated and authenticated contexts to surface endpoints where resource access is not properly constrained, aligning with OWASP API Top 10 (2023) A1: Broken Access Control.

To mitigate BOLA/IDOR with MongoDB in Laravel, enforce tenant or ownership checks in every query, use explicit projections to limit returned fields, and avoid exposing raw MongoDB identifiers in URLs where possible. Below are concrete, secure patterns with working MongoDB code examples for Laravel.

1. Enforce ownership with a scoped query

Always include the authenticated user’s identifier in the filter. If using a MongoDB collection directly via Laravel’s MongoDB integration, ensure the query includes user_id (or tenant_id) alongside the document identifier.

use MongoDB\Driver\Manager;
use MongoDB\BSON\ObjectId;

// Within a service class, after auth middleware has confirmed identity
public function getUserProfile(string $id, string $userId)
{
    $manager = new Manager('mongodb://localhost:27017');
    $filter = [
        '_id' => new ObjectId($id),
        'user_id' => $userId,
    ];
    $command = new \MongoDB\Driver\Command([
        'find' => 'users',
        'filter' => $filter,
        'projection' => ['email' => 0, 'password_hash' => 0], // explicit deny-list
    ]);
    $cursor = $manager->executeCommand('app_db', $command);
    $document = current($cursor->toArray());
    if (! $document) {
        abort(404);
    }
    return $document;
}

2. Use route binding with authorization

If leveraging route model binding, override the resolve method to include authorization logic rather than fetching by ID alone.

// In a custom binding resolver or repository
public function resolve($value, $field = null)
{
    $user = auth()->user();
    $document = $this->collection->findOne([
        '_id' => new \MongoDB\BSON\ObjectId($value),
        'user_id' => (string) $user->_id,
    ]);
    if (! $document) {
        abort(403, 'Unauthorized access to resource.');
    }
    return $document;
}

3. Apply strict field projections

Never return full documents to API consumers. Use projections to exclude sensitive fields at the database cursor level.

$cursor = $collection->find(
    ['user_id' => $user->id],
    ['projection' => ['username' => 1, 'email' => 1, '_id' => 1]]
);
foreach ($cursor as $doc) {
    // Only permitted fields are present
}

4. Validate and normalize identifiers

Avoid exposing sequential or guessable identifiers. Use UUIDs or hash IDs for public-facing references, and map them to MongoDB ObjectIds internally after authorization checks.

$publicId = $request->route('id');
$internalId = $this->idMapper->toInternal($publicId); // validates format
$user = $this->collection->findOne([
    '_id' => $internalId,
    'tenant_id' => auth()->user()->tenant_id,
]);

5. Centralize authorization logic

Implement policies or service classes that every controller uses, ensuring consistent checks across endpoints that interact with MongoDB documents.

class MongoDocumentPolicy
{
    public function view(string $documentId, string $userId): bool
    {
        $record = $this->collection->findOne([
            '_id' => new \MongoDB\BSON\ObjectId($documentId),
            'user_id' => $userId,
        ]);
        return $record !== null;
    }
}

By combining scoped queries, strict projections, validated identifiers, and centralized policies, Laravel applications using MongoDB can effectively prevent BOLA/IDOR while preserving the flexibility that MongoDB provides.