Dns Cache Poisoning in Adonisjs with Basic Auth

AdonisJS is a Node.js web framework that often relies on external HTTP clients to perform outbound requests, for example to call third-party APIs or internal services. When such requests use Basic Authentication, credentials are typically supplied via an Authorization header (e.g., base64(username:password)). Dns Cache Poisoning can affect this flow when the client performing the request resolves domain names using a shared or potentially compromised DNS resolver that does not adequately validate responses. An attacker who can poison DNS may redirect a legitimate hostname to a malicious server; because AdonisJS code may trust the resolved hostname and the Authorization header is automatically attached, the request can be redirected to an attacker-controlled endpoint with credentials included.

Consider an AdonisJS service that calls an external API using a hostname like api.partner.example and includes Basic Auth. If the DNS response for api.partner.example is poisoned to point to an attacker IP, the HTTP client will send the Authorization header to the attacker. This risk is not introduced by AdonisJS itself but by how the runtime environment resolves DNS; the framework will use whatever IP is returned for the hostname. The presence of Basic Auth increases the impact because credentials travel with the request, potentially exposing them to the party controlling the poisoned DNS path. Note that this is a network/upstream resolver issue; AdonisJS does not cache DNS internally in a way that introduces additional risk beyond standard Node.js behavior.

To understand exposure, correlate runtime findings with spec definitions when an OpenAPI document is available. middleBrick scans unauthenticated attack surface and, among its 12 parallel checks, flags SSRF and External Redirect issues that can combine with DNS weaknesses. For example, an endpoint that accepts a user-supplied hostname and performs outbound requests with Basic Auth can be abused to direct traffic internally or to malicious sites. middleBrick’s LLM/AI Security checks also verify whether system prompts or credentials are inadvertently reflected in outputs, which could compound risks if poisoned redirects lead to data exfiltration endpoints that log sensitive information.

Mitigate DNS Cache Poisoning risks in AdonisJS when using Basic Auth by reducing reliance on potentially poisoned hostname resolution and by ensuring credentials are not unnecessarily exposed. Prefer IP-based endpoints for high-value or high-risk calls when feasible, and pin certificates to prevent off-path attacks. Avoid constructing Authorization headers manually; use the built-in mechanisms provided by HTTP clients to ensure credentials are handled securely and are only sent to intended destinations.

Below are concrete AdonisJS examples showing insecure and secure approaches for HTTP calls that involve Basic Auth. These examples assume you are using an HTTP client like axios or the native node-fetch-style API common in AdonisJS providers.

Insecure: Manual header with dynamic hostname

// Risk: hostname resolved at runtime can be poisoned; credentials in header may be sent to malicious IP
const username = 'api_user';
const password = 's3cret';
const hostname = config.get('api.partnerHostname'); // user-influenced or configuration-driven
const auth = Buffer.from(`${username}:${password}`).toString('base64');

const response = await axios.get(`https://${hostname}/v1/resource`, {
  headers: { Authorization: `Basic ${auth}` }
});

Secure: Use Axios with auth field (preferred)

// Safer: Axios handles Authorization header construction; still depends on DNS for hostname resolution
const axios = require('axios');

const response = await axios.get('https://api.partner.example/v1/resource', {
  auth: {
    username: 'api_user',
    password: 's3cret'
  },
  httpsAgent: new (require('https').Agent)({ rejectUnauthorized: true })
});

Secure: Pin IP and validate TLS

// Mitigates DNS poisoning by using a static IP and strict TLS checks
const https = require('https');
const fs = require('fs');

const options = {
  hostname: '203.0.113.10', // pinned IP to reduce reliance on DNS
  port: 443,
  path: '/v1/resource',
  method: 'GET',
  auth: 'api_user:s3cret', // Node.js will encode to Basic Auth header
  rejectUnauthorized: true,
  ca: fs.readFileSync('/path/to/corporate-ca.pem') // explicit trusted CA
};

const req = https.request(options, (res) => {
  let data = '';
  res.on('data', (chunk) => data += chunk);
  res.on('end', () => console.log(data));
});
req.on('error', (err) => console.error(err));
req.end();

Secure: Validate hostname and use environment configuration

// Ensure hostname is static and validated; avoid dynamic user input
const ALLOWED_HOSTS = new Set(['api.partner.example', 'backup.partner.example']);
const hostname = config.get('api.partnerHostname');

if (!ALLOWED_HOSTS.has(hostname)) {
  throw new Error('Disallowed hostname');
}

// Use HTTP client with timeout and certificate pinning support where available
const response = await axios.get(`https://${hostname}/v1/resource`, {
  auth: {
    username: 'api_user',
    password: 's3cret'
  },
  timeout: 5000,
  httpsAgent: new (require('https').Agent)({ rejectUnauthorized: true })
});

Complement code-level fixes with operational practices: use encrypted configuration stores for credentials, rotate credentials regularly, and monitor DNS resolver integrity. middleBrick’s Pro plan supports continuous monitoring so that changes in API risk scores or findings like SSRF or External Redirect are surfaced promptly. For development workflows, the CLI enables quick scans from the terminal with middlebrick scan <url>, while the GitHub Action can enforce security gates in CI/CD pipelines.