static CURLcode smtp_state_auth_resp(struct connectdata *conn,
                                     int smtpcode,
                                     smtpstate instate)
{
  CURLcode result = CURLE_OK;
  struct Curl_easy *data = conn->data;
  struct smtp_conn *smtpc = &conn->proto.smtpc;
  saslprogress progress;

  (void)instate; /* no use for this yet */

  result = Curl_sasl_continue(&smtpc->sasl, conn, smtpcode, &progress);
  if(!result)
    switch(progress) {
    case SASL_DONE:
      state(conn, SMTP_STOP);  /* Authenticated */
      break;
    case SASL_IDLE:            /* No mechanism left after cancellation */
      failf(data, "Authentication cancelled");
      result = CURLE_LOGIN_DENIED;
      break;
    default:
      break;
    }

  return result;
}

The product performs operations on a memory buffer, but it reads from or writes to a memory location outside the buffer's intended boundary. This may result in read or write operations on unexpected memory locations that could be linked to other variables, data structures, or internal program data.