Broken Authentication in Strapi with Basic Auth

Strapi is a headless CMS that can be configured to use Basic Authentication for an API route or admin area. When Basic Auth is used incorrectly—or without additional protections—it contributes directly to broken authentication, a pattern reflected in the OWASP API Security Top 10. In a black-box scan, middleBrick tests unauthenticated endpoints and checks whether credentials can be enumerated or bypassed, and it can detect weak or missing defenses that enable attackers to gain unauthorized access.

Basic Authentication sends credentials as a base64-encoded string in the HTTP Authorization header. If the transport is not protected by TLS, these credentials are easily decoded. Even over HTTPS, storing credentials in source control or failing to rotate them creates a persistent risk. Strapi’s flexibility with custom routes means developers might expose an admin or data endpoint with Basic Auth but forget to enforce role-based access controls, leading to privilege escalation or data exposure. The combination of predictable admin paths (e.g., /admin) and weak credential management amplifies the impact of broken authentication.

middleBrick’s checks include authentication testing, authorization testing (BOLA/IDOR), and privilege escalation (BFLA). For Basic Auth–protected Strapi endpoints, the scanner verifies whether authentication is enforced consistently, whether tokens or credentials are leaked in responses or logs, and whether access control checks are applied per request. Without per-request validation, an attacker who obtains a valid credential pair can reuse it across sessions or endpoints, especially if session fixation or missing invalidation mechanisms are present.

Consider a Strapi API route that uses Basic Auth for an internal service but does not validate permissions for each operation. An attacker authenticates successfully but can then manipulate object IDs to access other users’ data (IDOR). This scenario would be flagged by the BOLA/IDOR check in middleBrick, which cross-references the OpenAPI specification with runtime behavior to confirm whether the implementation enforces ownership or role checks. Similarly, if the Basic Auth credentials are embedded in JavaScript bundles or exposed via an insecure CI/CD pipeline, the data exposure check can identify leakage before an attacker does.

To illustrate how Basic Auth is implemented in Strapi, the following code defines a custom route that uses HTTP Basic Auth. This example shows the structure but also highlights where security controls must be added to avoid broken authentication.

// ./api/custom/controllers/custom.js
'use strict';

const bcrypt = require('bcryptjs');

module.exports = {
  async verify(ctx) {
    const authHeader = ctx.request.header['authorization'];
    if (!authHeader || !authHeader.startsWith('Basic ')) {
      ctx.status = 401;
      ctx.body = { error: 'Unauthorized' };
      return;
    }

    const base64 = authHeader.split(' ')[1];
    const decoded = Buffer.from(base64, 'base64').toString('utf-8');
    const [username, password] = decoded.split(':');

    // In production, credentials should be stored hashed and validated against a service
    const validUser = { username: 'admin', passwordHash: await bcrypt.hash('SuperSecret123', 10) };

    const passwordMatch = await bcrypt.compare(password, validUser.passwordHash);
    if (!passwordMatch || username !== validUser.username) {
      ctx.status = 401;
      ctx.body = { error: 'Invalid credentials' };
      return;
    }

    // Authorization check should follow authentication
    if (!ctx.state.user || ctx.state.user.role !== 'admin') {
      ctx.status = 403;
      ctx.body = { error: 'Forbidden' };
      return;
    }

    ctx.body = { message: 'Authenticated and authorized' };
  },
};

This snippet demonstrates hashing the password and comparing it safely, but it omits protections such as rate limiting, audit logging, and secure header handling. In a real deployment, Strapi’s built-in admin should be protected with additional policies, and custom routes should inherit global middleware for authentication and authorization. middleBrick’s scan would evaluate whether these complementary controls are present and whether the endpoint is susceptible to credential theft or abuse through insecure consumption patterns.

Remediation focuses on enforcing transport security, protecting credentials, and adding strict authorization checks for every request. Basic Auth should be used only over HTTPS, with credentials stored as hashes and rotated regularly. Where possible, replace Basic Auth with token-based mechanisms that support revocation and short lifetimes.

Below is a revised example that includes HTTPS enforcement, secure credential storage, and explicit role checks. It also demonstrates how to integrate middleware to reduce risk of broken authentication in Strapi routes.

// ./api/custom/controllers/custom.js
'use strict';

const bcrypt = require('bcryptjs');

module.exports = {
  async verify(ctx) {
    // Enforce HTTPS in production
    if (process.env.NODE_ENV === 'production' && !ctx.request.secure) {
      ctx.status = 400;
      ctx.body = { error: 'HTTPS required' };
      return;
    }

    const authHeader = ctx.request.header['authorization'];
    if (!authHeader || !authHeader.startsWith('Basic ')) {
      ctx.status = 401;
      ctx.set('WWW-Authenticate', 'Basic realm="Secure Area"');
      ctx.body = { error: 'Unauthorized' };
      return;
    }

    const base64 = authHeader.split(' ')[1];
    const decoded = Buffer.from(base64, 'base64').toString('utf-8');
    const [username, password] = decoded.split(':');

    // Retrieve user from a secure data source
    const user = await strapi.entityService.findOne('api::user.user', {
      filters: { username },
    });
    if (!user) {
      ctx.status = 401;
      ctx.body = { error: 'Invalid credentials' };
      return;
    }

    const passwordMatch = await bcrypt.compare(password, user.password_hash);
    if (!passwordMatch) {
      ctx.status = 401;
      ctx.body = { error: 'Invalid credentials' };
      return;
    }

    // Ensure per-request authorization
    if (user.role !== 'admin') {
      ctx.status = 403;
      ctx.body = { error: 'Forbidden' };
      return;
    }

    // Attach user to request state for downstream middleware
    ctx.state.user = { id: user.id, role: user.role };
    ctx.body = { message: 'Authenticated and authorized' };
  },
};

Key remediation steps include enforcing HTTPS, avoiding hardcoded credentials, hashing passwords, validating credentials against a data source, and confirming authorization on each request. middleBrick’s scans help verify that these controls are present by testing authentication boundaries and checking for IDOR or privilege escalation across endpoints. For teams using the Pro plan, continuous monitoring can alert on deviations such as missing HTTPS or weak credential storage, while the GitHub Action can fail builds if a scan detects authentication issues before deployment.

When Basic Auth must be used, rotate credentials frequently, avoid embedding them in source code, and pair with additional mechanisms such as IP allowlists or short-lived tokens. The MCP Server allows developers to scan APIs directly from their coding environment, catching misconfigurations early in the development cycle.