Jwt Misconfiguration in Adonisjs with Dynamodb

When an AdonisJS application uses JSON Web Tokens (JWT) for authentication and stores session or user metadata in DynamoDB, specific misconfigurations can expose the unauthenticated attack surface that middleBrick scans. JWT misconfiguration often involves missing or weak audience (aud) validation, insecure token storage on the client, and overly permissive IAM policies for DynamoDB access. If an API endpoint relies on JWT claims to authorize DynamoDB operations without verifying token scope or binding the token to the request context, an attacker can manipulate claims to access or modify other users' data stored in DynamoDB.

For example, if the token does not include a tenant or user identifier claim, or if the identifier is present but not validated against the DynamoDB key condition expressions, an attacker can substitute their own user ID in path parameters or query inputs. Because middleBrick tests unauthenticated endpoints, it can detect endpoints where JWT is accepted but not properly enforced, or where DynamoDB queries rely on unchecked user input derived from the token. This combination can lead to IDOR/BOLA, privilege escalation via BFLA, and unsafe consumption findings. The scanner also checks whether sensitive data exposed by DynamoDB responses is returned without proper authorization controls, which can amplify the impact of JWT misconfiguration.

Real-world attack patterns include token substitution to access another user's DynamoDB item by changing a user ID in the request, or exploiting missing aud validation to present a token issued for a different service. If the application uses DynamoDB with fine-grained access control but does not enforce ownership checks in the data layer, middleBrick will flag the endpoint with high severity for BOLA/IDOR and Property Authorization. The presence of JWT in the request without corresponding DynamoDB-level authorization logic is a strong indicator that the unauthenticated attack surface includes authorization bypass risks that can be confirmed during the scan.

To remediate JWT misconfiguration when using DynamoDB in AdonisJS, enforce strict token validation and bind DynamoDB operations to the authenticated subject. Always validate the aud and iss claims, and ensure the user identifier from the JWT is used consistently in DynamoDB key condition expressions. Avoid trusting path parameters or query strings to identify the resource owner; instead derive the resource owner from the validated JWT claims and use them in conditional expressions in DynamoDB queries.

Below is a concrete example of secure DynamoDB access in AdonisJS using the AWS SDK. The code retrieves the user identifier from a verified JWT and uses it in a DynamoDB GetItem key, ensuring the request can only access the item belonging to the authenticated user.

import { HttpContextContract } from '@ioc:Adonis/Core/HttpContext'
import { DynamoDBClient, GetItemCommand } from '@aws-sdk/client-dynamodb'
import { unmarshall } from '@aws-sdk/util-dynamodb'
import jwt from 'jsonwebtoken'

export default class SessionsController {
  private readonly client = new DynamoDBClient({ region: 'us-east-1' })

  public async showProfile({ request, response }: HttpContextContract) {
    const authHeader = request.header('authorization')
    if (!authHeader?.startsWith('Bearer ')) {
      return response.unauthorized()
    }
    const token = authHeader.split(' ')[1]
    let payload: any
    try {
      payload = jwt.verify(token, process.env.JWT_SECRET as string, {
        audience: 'my-api.example.com',
        issuer: 'adonisjs-app',
      })
    } catch (error) {
      return response.unauthorized()
    }

    const userId = payload.sub
    if (!userId) {
      return response.badRequest({ error: 'invalid_token' })
    }

    const command = new GetItemCommand({
      TableName: process.env.USERS_TABLE,
      Key: {
        user_id: { S: userId },
      },
    })

    const result = await this.client.send(command)
    if (!result.Item) {
      return response.notFound({ error: 'user_not_found' })
    }

    const user = unmarshall(result.Item)
    return response.ok(user)
  }
}

This example validates JWT audience and issuer, extracts the subject (sub) for the DynamoDB key, and uses a parameterized key condition to avoid injection or confused deputy issues. For queries that involve user-owned resources, always enforce ownership by including the user identifier in the key expression and avoid using request-supplied identifiers for item keys.

In scan reports, middleBrick will highlight endpoints that accept JWT but do not enforce ownership checks or that expose DynamoDB errors that can reveal item existence. Remediation guidance typically includes adding explicit ownership validation, tightening IAM policies to limit scope to user-specific items, and ensuring sensitive fields are not returned without authorization. By addressing these DynamoDB-specific controls, you reduce the risk of IDOR and privilege escalation that can be detected as part of the 12 security checks run by middleBrick.