Or Pocahontas. None is dishonest in an absolut term, but if we get picky...

Cinderella "hides" the fact that she was at the ball. Again, she doesn´t lie, but she´s not being openly honest to her stepmother (which is a good decision, but rules her out of this pick)

Aurora tells the animals in the forest she "tricked" her aunts and met stranger... in her dream. She hides this little dream, which is no big deal, but it´s something, and I can´t think anything for Snow White. Correct me if I´m wrong.

Ariel keeps a whole cavern full of secrets from her family.

Belle tricks Cogsworth into letting her see the castle, goes to the west wing and moreover, breaks her promise. That last one definetely rules her out.

Jasmine is very outspoken, but she can be deceitful if she wants... take her seduction of Jafar. That wasn´t honest.

Mulan actually dresses like a man. She has to lie to survive in the army.

Tiana wishes upon a star after tellind Lottie it´s ridicoulous.

Rapunzel keeps her promises, unlike Belle, but she lies to Mother Gothel by asking her a present that would send her away for some time.

Pocahontas never lies, I think. She tries to tell her father about John Smith. In a way though, she hides her encounters with him, that´s why I choose Snow White.

^that. except Pocahontas does ask her friend to lie for her.

Pocahontas asks Nakoma to lie for her, sneaks around her dads back. All the princesses do something dishonest except for Snow.