Broken Access Control in Adonisjs with Dynamodb

Broken Access Control occurs when authorization checks are missing, incomplete, or bypassed, allowing a user to access resources or actions they should not be able to. Using AdonisJS with DynamoDB can unintentionally create or expose these vulnerabilities when application-level guards are not enforced consistently across the request lifecycle and when data access patterns assume isolation that DynamoDB does not provide automatically.

AdonisJS is a Node.js framework that encourages a model-based approach, but it does not enforce authorization out of the box. Developers must explicitly implement policies and guards. When integrating DynamoDB as the persistence layer, queries are typically constructed using the AWS SDK for JavaScript (v3). If the application builds DynamoDB requests by interpolating user input — such as using a request parameter as a partition key or as a filter expression without validating ownership — attackers can manipulate these values to access other users’ data or administrative resources.

Consider an endpoint like GET /documents/:documentId. If the route handler retrieves the document ID from the params, builds a GetCommand with that ID, and executes it directly against DynamoDB without confirming that the authenticated user owns the document, the BOLA (Broken Object Level Authorization) vulnerability exists. The same risk appears in list or search endpoints where a Scan or Query uses a filter like userId = :uid but the :uid is taken from the request rather than from the authenticated identity. Because DynamoDB does not enforce row-level permissions natively, it is the application’s responsibility to ensure every request includes a strict ownership check tied to the requester’s identity.

In AdonisJS, middleware and policies are the typical enforcement points. A common misconfiguration is applying a policy only to certain routes while other routes that interact with DynamoDB remain unprotected. Additionally, if the application caches IAM credentials at a broad scope (e.g., per-service rather than per-request context), a compromised token or misconfigured assumption can allow broad read or write access across many DynamoDB tables. The framework’s IoC container and bindings do not automatically scope data access to the current user, so developers must explicitly pass the user identifier into data layer methods and enforce it in DynamoDB request construction.

Attack patterns specific to this combination include IDOR via predictable keys (e.g., using sequential IDs as partition keys), privilege escalation through administrative API calls, and data exfiltration via manipulated filter expressions. Because DynamoDB supports complex queries and secondary indexes, an attacker who can inject a different filter or key condition may retrieve large datasets if the application does not validate scope. The 12 security checks in middleBrick, including BOLA/IDOR and Property Authorization, are designed to detect these issues by correlating runtime requests with OpenAPI specifications and observed behavior, highlighting where access controls are missing or misapplied.

Remediation focuses on ensuring every DynamoDB request is scoped to the authenticated user and validated against the application’s authorization model. Below are concrete, working examples for AdonisJS that demonstrate how to enforce ownership and apply least privilege when using DynamoDB.

1. Scope reads and writes to the authenticated user’s data by using the user identifier from the auth session as the partition key. Avoid using request-supplied identifiers for ownership checks.

// resources/controllers/DocumentController.ts
import { HttpContextContract } from '@ioc:Adonis/Core/HttpContext'
import { DynamoDBClient, GetCommand } from '@aws-sdk/client-dynamodb'
import { marshall } from '@aws-sdk/util-dynamodb'

export default class DocumentsController {
  private ddb = new DynamoDBClient({})

  public async show({ auth, params, response }: HttpContextContract) {
    const user = auth.getUserOrFail()
    // Use the authenticated user’s ID as the partition key, not the request param
    const command = new GetCommand({
      TableName: 'Documents',
      Key: marshall({
        userId: user.id,
        documentId: params.id,
      }),
    })

    const item = await this.ddb.send(command)
    if (!item.Item) {
      return response.notFound()
    }
    return item.Item
  }
}

2. Enforce ownership at the policy level and reuse it across controllers. Policies in AdonisJS can receive the user and the target record (or key components) to make authorization explicit.

// policies/document_policy.ts
import { Document } from 'App/Models/Document'
import { HttpContextContract } from '@ioc:Adonis/Core/HttpContext'

export default class DocumentPolicy {
  public async authorizeView(user: any, documentId: string) {
    // Here you would fetch minimal metadata (e.g., via a lightweight DynamoDB query)
    // to confirm ownership without returning sensitive data
    const { DynamoDBClient, GetCommand } = require('@aws-sdk/client-dynamodb')
    const { marshall, unmarshall } = require('@aws-sdk/util-dynamodb')

    const ddb = new DynamoDBClient({})
    const command = new GetCommand({
      TableName: 'Documents',
      Key: marshall({
        userId: user.id,
        documentId,
      }),
      ProjectionExpression: 'userId',
    })

    const result = await ddb.send(command)
    return !!result.Item
  }
}

3. For list or search endpoints, always use the authenticated user’s ID as a required filter in the query key condition expression. Avoid client-supplied filter values for ownership. If using a Global Secondary Index (GSI), design the partition key to align with user-based access patterns.

// resources/controllers/DocumentsController.ts
import { HttpContextContract } from '@ioc:Adonis/Core/HttpContext'
import { DynamoDBClient, QueryCommand } from '@aws-sdk/client-dynamodb'
import { marshall, unmarshall } from '@aws-sdk/util-dynamodb'

export default class DocumentsController {
  private ddb = new DynamoDBClient({})

  public async index({ auth, request, response }: HttpContextContract) {
    const user = auth.getUserOrFail()
    const page = request.q().page || 1
    const limit = Math.min(request.q().limit || 10, 50)

    const command = new QueryCommand({
      TableName: 'Documents',
      IndexName: 'UserIdIndex', // GSI with userId as partition key
      KeyConditionExpression: 'userId = :uid',
      ExpressionAttributeValues: marshall({ ':uid': user.id }),
      Limit: limit,
      ExclusiveStartKey: page > 1 ? marshall({ documentId: request.q().after || '' }) : undefined,
    })

    const result = await this.ddb.send(command)
    return {
      data: (result.Items || []).map((item) => unmarshall(item)),
      pagination: {
        page,
        limit,
        next: result.LastEvaluatedKey ? '?page=' + (page + 1) : null,
      },
    }
  }
}

4. Avoid using DynamoDB Scan in production endpoints that are user-scoped; if Scan is necessary for administrative operations, require an additional authorization check and ensure it runs under a restricted IAM role. Use IAM policies and resource-based permissions to limit what each application role can do, and keep credentials scoped to the minimum required permissions.

5. In AdonisJS, bind authenticated user information into the request context so that services and controllers can rely on a consistent identity. Combine this with input validation to reject malformed or suspicious IDs before they reach DynamoDB. These practices reduce the risk of IDOR and privilege escalation by design rather than by ad-hoc checks.