apache/hadoop · error · AuthenticationException

Error validating LDAP user: a null or blank username has bee

Error message

Error validating LDAP user: a null or blank username has been provided

What it means

Error "Error validating LDAP user: a null or blank username has been provided" thrown in apache/hadoop.

Source

Thrown at hadoop-common-project/hadoop-auth/src/main/java/org/apache/hadoop/security/authentication/server/LdapAuthenticationHandler.java:212

    } else {
      authorization =
          authorization.substring(HttpConstants.BASIC.length()).trim();
      final Base64 base64 = new Base64(0);
      // As per RFC7617, UTF-8 charset should be used for decoding.
      String[] credentials = new String(base64.decode(authorization),
          StandardCharsets.UTF_8).split(":", 2);
      if (credentials.length == 2) {
        token = authenticateUser(credentials[0], credentials[1]);
        response.setStatus(HttpServletResponse.SC_OK);
      }
    }
    return token;
  }

  private AuthenticationToken authenticateUser(String userName,
      String password) throws AuthenticationException {
    if (userName == null || userName.isEmpty()) {
      throw new AuthenticationException("Error validating LDAP user:"
          + " a null or blank username has been provided");
    }

    // If the domain is available in the config, then append it unless domain
    // is already part of the username. LDAP providers like Active Directory
    // use a fully qualified user name like foo@bar.com.
    if (!hasDomain(userName) && ldapDomain != null) {
      userName = userName + "@" + ldapDomain;
    }

    if (password == null || password.isEmpty() ||
        password.getBytes(StandardCharsets.UTF_8)[0] == 0) {
      throw new AuthenticationException("Error validating LDAP user:"
          + " a null or blank password has been provided");
    }

    // setup the security principal
    String bindDN;

View on GitHub (pinned to 2add963021)

Solutions

1. Provide a non-empty username in the authentication request.

Example fix

Send a valid 'userName' parameter in the login request.

When it happens

Trigger: Raised at runtime when the documented precondition or configuration requirement for this operation is violated.

Common situations: Misconfigured or missing property, invalid user input, or calling the API before its prerequisites are met.

AI-assisted analysis of apache/hadoop@2add963021 (2026-08-22). Data as JSON: /api/errors/0b230f031a465971. Report an issue: GitHub.