"As you can imagine it has gone ballistic," Ms Asher said. "They are just sending in videos of themselves for starters - we just need to know what their voice is like."
CNA is looking for a Maori or Pasifika teenage girl, aged between 14 and 19, who can bring Moana's attributes - "smart, passionate and funny" - to life.
A strong singing voice is a must, and hopefuls have been instructed to send a video of themselves singing part of a song and explaining why they would make a great Moana.
"We are looking for someone with a very special voice. I think we'll know when we come across that special voice," Ms Asher said.
"It's more than just being a great singer or actor, they have to have a voice that can carry an entire movie."
CNA had spent the previous two weeks looking at known talent but had now thrown open the casting call to ensure nobody "hiding under a rock" was missed.
"We were going to have an open call, but I can see it would just be impossible - the queue would go around too many blocks."
The CG-animated flick Moana, directed by Ron Clements and John Musker, will open on November 23, 2016. Set in the ancient South Pacific world of Oceania, it follows a spirited Polynesian princess who sets sail in search of a fabled island, meeting the Maori demi-god Maui along the way.
Kiwi film-maker Taika Waititi is involved in the film, having written the original script.
Read more:
• Taika Waititi behind Disney script 'Moana'
• Moana Tapaleao: Finally - a fantasy Pasifika can relate to
• Ten things you didn't know about Disney princesses
Asked if Moana would be played by a New Zealander, Ms Asher said there were large Polynesian populations elsewhere, including in the United States.
CNA was casting for the part of Moana and some other adult characters as well, but the wide casting was for the lead role.
Hopefuls should get their video submission in as soon as possible, Ms Asher said.
