Api Rate Abuse in Adonisjs with Basic Auth

Rate abuse in AdonisJS when Basic Auth is used centers on how authentication state and request volume intersect. Basic Auth sends credentials in an HTTP header on every request. If an API endpoint relies solely on Basic Auth for identity but does not enforce per-identity rate limits, an attacker can brute-force credentials or flood a specific user’s token/identifier without throttling.

In AdonisJS, routes often resolve user identity from the auth header via an auth provider or an explicit check in the controller. Without a corresponding rate-limiting layer tied to the resolved identity (or to the endpoint itself), an attacker can submit a high volume of unauthenticated or low-cost authenticated requests. This can lead to enumeration (testing many usernames or IDs), credential stuffing, or denial-of-service via resource exhaustion on the database or downstream services. The scanner flags this as BFLA / Privilege Escalation and Rate Limiting findings because the control boundary (authentication) does not enforce usage constraints at the same granularity.

Basic Auth also lacks built-in replay protection or nonce mechanisms. If an API does not add idempotency keys, timestamps, or other anti-abuse signals, an attacker can repeat captured requests to amplify impact. Because middleBrick tests unauthenticated attack surfaces and authenticated scenarios where credentials are provided, it can detect when rate controls are absent or misaligned with the auth mechanism. Findings include missing per-user limits, coarse global limits, and lack of identifier-based throttling after authentication.

When scanning an AdonisJS endpoint with Basic Auth, middleBrick’s Rate Limiting check correlates the auth context with observed behavior. For example, if 200 requests arrive in 10 seconds from the same IP but represent 50 distinct usernames via Basic Auth, the scanner highlights the absence of per-identity throttling. This supports the BOLA/IDOR and Privilege Escalation checks, as weak rate controls can enable horizontal or vertical abuse. Remediation guidance focuses on tying rate limits to the authenticated subject (e.g., username or user ID), adding sliding windows, and instrumenting meaningful identifiers rather than relying on IP alone.

To secure AdonisJS APIs using Basic Auth, couple authentication with explicit rate-limiting logic tied to the identity extracted from the credentials. Below is a realistic, syntactically correct example that demonstrates middleware performing Basic Auth verification and applying per-user rate limits using an in-memory map for simplicity; in production, replace this with a distributed store like Redis.

// middleware/basic_auth_rate_limiter.ts
import { Exception } from '@poppinss/utils'
import { HttpContextContract } from '@ioc:Adonis/Core/HttpContext'

// Simple in-memory store; production should use Redis or similar
const requestCounts = new Map()

export default class BasicAuthRateLimiter {
  public async handle({ request, response, auth }: HttpContextContract) {
    const credentials = request.authUser
    if (!credentials || !credentials.username) {
      return response.unauthorized({ message: 'Missing credentials' })
    }

    const key = `${credentials.username}:${request.url()}`
    const now = Date.now()
    const windowMs = 60_000 // 1 minute
    const maxRequests = 30

    const record = requestCounts.get(key)
    if (record) {
      if (now < record.resetAt) {
        if (record.count >= maxRequests) {
          throw new Exception('Too many requests', 429, 'RATE_LIMIT_EXCEEDED')
        }
        record.count += 1
      } else {
        record.count = 1
        record.resetAt = now + windowMs
      }
    } else {
      requestCounts.set(key, { count: 1, resetAt: now + windowMs })
    }

    // Proceed to route handler
  }
}

Register the middleware and apply it to routes that require protection. Combine with AdonisJS built-in auth to validate credentials before the rate limiter runs, ensuring the limit applies per authenticated identity.

// start/routes.ts
import Route from '@ioc:Adonis/Core/Route'
import BasicAuthRateLimiter from '../middleware/basic_auth_rate_limiter'

Route.group(() => {
  Route.get('/profile', async ({ auth, response }) => {
    const user = auth.getUserOrFail()
    return { user: { username: user.username, email: user.email } }
  }).middleware(['auth:basic', 'BasicAuthRateLimiter'])

  Route.post('/data', async ({ auth, request, response }) => {
    const user = auth.getUserOrFail()
    const body = request.only(['payload'])
    return { username: user.username, received: body.payload }
  }).middleware(['auth:basic', 'BasicAuthRateLimiter'])
}).prefix('api/v1')

On the auth provider side, ensure your Basic Auth validator resolves the user and attaches a stable identifier (username or user ID). This identifier becomes the key component of your rate-limiting logic, making limits meaningful and aligned with the authenticated subject. Avoid relying on IP-based limits alone when Basic Auth is in use, as shared IPs can mask abusive behavior from distinct users.

For production, integrate a persistent backend store to maintain counts across instances and restarts. The pattern above illustrates the concept; adapt it to use Redis or a database-backed limiter, and enforce stricter windows for sensitive endpoints. This approach directly addresses the Rate Limiting and BFLA / Privilege Escalation findings that middleBrick surfaces when Basic Auth lacks per-identity throttling.