Broken Access Control in Laravel with Basic Auth

Broken Access Control occurs when authorization checks are missing or incorrectly applied, allowing authenticated users to access or modify resources that should be restricted. In Laravel, using HTTP Basic Authentication without explicit role- or permission-based checks can inadvertently expose privileged endpoints to any authenticated user, including low-privilege accounts.

When Basic Auth is used, Laravel typically identifies the user via the auth:user middleware or via a custom guard configured for basic auth. If routes that manage users, billing, or administrative functions rely only on the auth middleware (e.g., Route::middleware('auth:sanctum|basic')) and omit granular policy or gate checks, any authenticated user can invoke sensitive actions. This is a classic Broken Access Control failure because authentication (who you are) is not coupled with proper authorization (what you are allowed to do).

Consider an endpoint that deletes other user accounts or modifies roles. If it only requires authentication and does not assert that the authenticated user has an admin role, a compromised or low-privilege account can escalate privileges by invoking the endpoint. In API contexts, this risk is amplified because Basic Auth credentials are often embedded in scripts or CI tools; if leaked, they grant broad access without additional friction.

Another scenario involves horizontal access control: User A can view or edit User B’s data because the route binds an ID (e.g., /api/users/{id}) but does not verify that the authenticated user owns that resource. With Basic Auth, the user object is available via auth()->user(), but if the route does not compare the bound ID to the authenticated user’s ID, unauthorized cross-user access becomes possible.

middleBrick’s checks for BOLA/IDOR and Property Authorization highlight these gaps by correlating authentication state with runtime access patterns. Even when Basic Auth is in use, the scanner tests whether endpoints enforce proper ownership or role checks and surfaces findings when authorization is missing or misaligned with least-privilege principles.

To fix Broken Access Control when using Basic Auth, combine route authentication with explicit authorization checks, and ensure per-request user validation for resource ownership.

1. Use auth middleware with a dedicated guard (optional but recommended)

Configure a basic auth guard in config/auth.php and reference it in routes to avoid accidentally using session-based guards:

// config/auth.php
return [
    'guards' => [
        'api_basic' => [
            'driver' => 'basic',
            'provider' => 'users',
        ],
    ],
    'providers' => [
        'users' => [
            'driver' => 'eloquent',
            'model' => App\Models\User::class,
        ],
    ],
];

2. Apply role/permission checks via policies or gates

Create a policy and attach it to routes to ensure only users with the correct role can perform sensitive actions:

// app/Policies/UserPolicy.php
namespace App\Policies;

use App\Models\User;
use Illuminate\Auth\Access\HandlesAuthorization;

class UserPolicy
{
    use HandlesAuthorization;

    public function delete(User $user, User $target)
    {
        return $user->is_admin;
    }

    public function view(User $user, User $target)
    {
        return $user->id === $target->id || $user->is_admin;
    }
}

// Register policy (e.g., in AuthServiceProvider)
protected $policies = [
    User::class => \App\Policies\UserPolicy::class,
];

Then enforce in routes:

use Illuminate\Support\Facades\Route;

Route::middleware('auth:api_basic')->group(function () {
    Route::delete('/users/{user}', [UserController::class, 'destroy'])
         ->middleware('can:delete,user');
});

3. Enforce ownership checks in controller actions

Even when using policies, explicitly compare resource ownership in the controller for clarity and defense in depth:

use App\Models\User;
use Illuminate\Http\Request;

class UserController extends Controller
{
    public function show(User $requested, int $id)
    {
        $user = User::findOrFail($id);

        // Horizontal access control: ensure requesting user matches target or is admin
        if ($requested->id !== $user->id && ! $requested->is_admin) {
            abort(403, 'Unauthorized action.');
        }

        return $user;
    }
}

4. Validate route binding with implicit model binding and explicit checks

Use implicit binding with policy-based authorization, and add route model binding constraints where applicable:

use Illuminate\Foundation\Support\Providers\RouteServiceProvider;
use Illuminate\Support\Facades\Route;

Route::model('user', \App\Models\User::class);

Route::middleware('auth:api_basic')->group(function () {
    Route::get('/users/{user}', function (\App\Models\User $user) {
        if (auth()->id() !== $user->id && ! auth()->user()->is_admin) {
            abort(403);
        }
        return $user;
    });
});

5. Avoid relying on Basic Auth alone for authorization

Basic Auth provides authentication, not authorization. Always pair it with role checks, policies, or gates. Do not use group or IP-based restrictions as a substitute for per-request authorization.

middleBrick’s scans for BOLA/IDOR and Property Authorization surface missing checks by correlating authenticated identity with endpoint behavior, helping you identify routes that rely solely on Basic Auth without proper authorization logic.