Insecure Design in Adonisjs with Mongodb

Insecure design in an AdonisJS application using MongoDB typically arises from trusting client-supplied data to drive query construction, insufficient authorization at the domain-object level, and weak schema constraints. When these design choices intersect with MongoDB behavior, they enable attackers to bypass intended access controls and read or modify data that should be isolated.

One common pattern is directly passing request query parameters or body fields into MongoDB queries without normalization or strict allowlisting. For example, using user input to dictate which fields are projected or which nested paths are traversed can lead to Excessive Data Exposure and Insecure Direct Object References (IDOR). An attacker can manipulate parameters such as ?profileFields=password,email to retrieve sensitive fields that the application intended to keep internal.

Authorization issues often stem from incomplete ownership checks. AdonisJS controllers may enforce that a user is authenticated but fail to confirm that the targeted resource (e.g., a user document or a related tenant record) actually belongs to the requesting subject. Because MongoDB does not enforce row-level security natively, it is the application’s responsibility to embed the actor’s identity into every query. Neglecting this results in BOLA/IDOR where one user can operate on another’s documents by guessing valid ObjectIds.

Schema-less flexibility compounds these risks. Without runtime validation of document shape, an attacker can inject unexpected fields that change behavior, such as adding isAdmin: true during updates or leveraging dot-notation to modify nested settings. In AdonisJS, if field-level mass assignment is not explicitly guarded, this can escalate privileges or violate Property Authorization assumptions. Similarly, unbounded nested updates or poorly designed aggregation pipelines can lead to Server-Side Request Forgery (SSRF) when user-controlled values are used in lookup stages or $http-like operations within application logic.

Insecure default configurations also contribute. For instance, if MongoDB connections are established with elevated privileges and AdonisJS does’t enforce the principle of least privilege per service, compromised application code may perform destructive writes. Lack of field-level encryption for sensitive attributes (such as tokens or PII) in MongoDB increases Data Exposure risk, especially if backups or logs are not similarly protected. These design decisions highlight the importance of modeling security into the interaction between AdonisJS controllers, services, and MongoDB queries rather than relying on network-level perimeter defenses.

Remediation centers on strict input validation, explicit ownership checks, controlled query construction, and schema governance. Always treat user input as untrusted and transform it before using it in MongoDB operations.

1) Parameter allowlisting and schema validation
Use AdonisJS schema validation to ensure only expected fields are present and to coerce types. For projection parameters, define an enum of allowed fields and reject anything else.

import { schema, rules } from '@ioc:Adonis/Core/Validator'
import { HttpContextContract } from '@ioc:Adonis/Core/HttpContext'

const profileFieldsSchema = schema.create({
  fields: schema.enum.optional(['username', 'email', 'bio'], [rules.defined()]),
})

export async function profileFieldsValidator({ request, reporter }: { request: any, reporter: any }) {
  await request.validate({ schema: profileFieldsSchema })
}

In your controller, use the validated enum to build a safe projection:

import Profile from 'App/Models/Profile'

export default class ProfilesController {
  public async show({ request, auth }: HttpContextContract) {
    const { fields } = await profileFieldsValidator({ request, reporter: request.reporter })
    const user = auth.user! // authenticated actor
    const allowedProjection: Record = { _id: 0 }
    ;(fields || ['username', 'email']).forEach((f) => {
      allowedProjection[f] = 1
    })
    const profile = await Profile.query()
      .where('userId', user.id)
      .project(allowedProjection)
      .preload('avatar')
      .firstOrFail()
    return profile
  }
}

This ensures only whitelisted fields are returned and the query is scoped to the authenticated user’s document.

2) Ownership checks and scoped queries
Embed the actor identifier directly in the query to enforce BOLA/IDOR protection. Never trust URL or body IDs alone.

import Env from '@ioc:Adonis/Core/Env'
import User from 'App/Models/User'

export default class DocumentsController {
  public async show({ params, auth }: HttpContextContract) {
    const document = await Document.query()
      .where('id', params.id)
      .where('ownerId', auth.user!.id)
      .preload('attachments')
      .firstOrFail()
    return document
  }
}

For MongoDB, ensure your filter includes tenant or user identifiers:

import { Db } from 'mongodb'
import { HttpContextContract } from '@ioc:Adonis/Core/HttpContext'

export default class TenantDataController {
  constructor(private db: Db) {}

  public async listCollections({ auth }: HttpContextContract) {
    const cursor = this.db.collection('datasets')
      .find({
        tenantId: auth.user!.tenantId,
        isArchived: { $ne: true },
      })
      .toArray()
    return cursor
  }
}

Always scope by tenantId or ownerId to prevent cross-tenant reads/writes.

3) Controlled updates and schema governance
Prevent unwanted field injection by using explicit update shapes and avoiding positional operators on user-controlled paths. Define update schemas and prefer $set over dynamic paths.

import { schema } from '@ioc:Adonis/Core/Validator'

const updateProfileSchema = schema.create({
  data: schema.object({
    username: schema.string.optional(),
    email: schema.string.optional([rules.email()]),
    bio: schema.string.optional(),
  }),
})

export async function updateProfileValidator({ request }: { request: any }) {
  return request.validate({ schema: updateProfileSchema })
}

In the controller, map validated fields to a safe $set object:

export default class ProfilesController {
  public async update({ request, auth, response }: HttpContextContract) {
    const body = await updateProfileValidator({ request })
    const result = await Profile.query()
      .where('userId', auth.user!.id)
      .update({
        $set: {
          username: body.data.username,
          email: body.data.email,
          bio: body.data.bio,
        },
      })
    return result
  }
}

Avoid passing raw user input to $set or to aggregation $lookup stages. If dynamic field paths are required, validate them against an allowlist of known safe values.

4) Least privilege and connection hardening
Configure MongoDB accounts with minimal permissions per AdonisJS service. If using MongoDB client directly, avoid operating as a superuser and prefer role-based access that matches the app’s needs (e.g., readWrite on specific collections only).