Ldap Injection in Adonisjs with Jwt Tokens

Ldap Injection occurs when untrusted input is concatenated directly into an LDAP query, allowing an attacker to manipulate the query structure. In AdonisJS applications that integrate LDAP for authentication but then issue JWT Tokens for session management, the risk is a two-stage attack surface: an LDAP injection can bypass authentication or retrieve credentials, and the resulting success can be used to forge or escalate JWT Tokens.

Consider an AdonisJS controller that binds a user-supplied username to an LDAP filter without sanitization:

const ldap = require('ldapjs');
const client = ldap.createClient({ url: 'ldap://example.com' });

async login({ request }) {
  const { username, password } = request.only(['username', 'password']);
  const filter = `(uid=${username})`; // Unsafe direct concatenation
  const conn = await client.bind('cn=admin,dc=example,dc=com', 'adminpass');
  const res = await conn.search('ou=users,dc=example,dc=com', { filter });
  // ... handle res
}

If username contains )(uid=*), the filter becomes (uid=)(uid=*)), potentially returning all users. Successful LDAP authentication in this scenario can lead the application to issue a JWT Tokens session without verifying that the token’s claims are bound to a verified, least-privilege identity. Moreover, if the application embeds LDAP-derived user attributes (e.g., groups or roles) into the JWT Tokens payload without strict validation, an attacker can inject group memberships or roles directly into the token, enabling privilege escalation.

The combination is particularly dangerous because LDAP injection compromises the identity source, while JWT Tokens are often treated as authoritative once issued. An attacker who exploits LDAP injection can gain a valid bind and then request a JWT Tokens with manipulated claims, or they can tamper with the token issuance logic by controlling the LDAP data that feeds it.

Real-world attack patterns mirror CVE-like scenarios where improper input sanitization in LDAP filters leads to unauthorized data retrieval. This maps to the BOLA/IDOR and Unsafe Consumption checks in middleBrick, which would flag the absence of strict input validation and over-permissive token claims. The scanner would highlight the missing sanitization of the username parameter and the unchecked propagation of LDAP attributes into JWT Tokens claims.

Remediation focuses on two pillars: strict input validation for LDAP queries and disciplined claims handling for JWT Tokens. Never directly interpolate user input into LDAP filters. Use parameterized filters or an LDAP escape function.

Secure LDAP query example in AdonisJS:

const ldap = require('ldapjs');
const client = ldap.createClient({ url: 'ldap://example.com' });

function escapeLDAP(str) {
  return str.replace(/[\\*()"+\\000]/g, (match) => {
    return '\\' + match.charCodeAt(0).toString(16).padStart(2, '0');
  });
}

async login({ request }) {
  const { username, password } = request.only(['username', 'password']);
  const safeUsername = escapeLDAP(username);
  const filter = `(uid=${safeUsername})`;
  const conn = await client.bind('cn=admin,dc=example,dc=com', 'adminpass');
  const res = await conn.search('ou=users,dc=example,dc=com', { filter });
  // ... handle res
}

For JWT Tokens, ensure that claims are derived from a trusted source and not directly from LDAP attributes without verification. Use a library like jsonwebtoken and validate scopes and roles against a whitelist.

const jwt = require('jsonwebtoken');

function generateToken(user) {
  // Whitelist roles/groups instead of passing LDAP attributes directly
  const allowedRoles = ['user', 'admin'];
  const roles = Array.isArray(user.roles) ? user.roles.filter(r => allowedRoles.includes(r)) : [];
  
  return jwt.sign(
    {
      sub: user.uid,
      name: user.cn,
      roles: roles, // Controlled, minimal claims
      iss: 'adonisjs-app',
      aud: 'api.example.com'
    },
    process.env.JWT_SECRET,
    { algorithm: 'HS256', expiresIn: '1h' }
  );
}

Additionally, enforce strict schema validation on the JWT Tokens payload on the resource server side. Do not trust the token’s contents implicitly when making authorization decisions. middleBrick’s Property Authorization and BOLA checks would validate that token claims are constrained and that over-provisioned permissions are not accepted. The Pro plan’s continuous monitoring can alert you if tokens with unexpected claims appear in your API traffic, while the CLI can be integrated into scripts to verify that your token generation logic remains hardened.