It is in Indo-Tibetan Mahayana. "The eighteen root downfalls: The root downfalls are more serious than the secondary downfalls because, if we incur a root downfall, we actually break our Bodhisattva vows, whereas, if we incur a secondary downfall, we damage our vows but we do not completely break them. Altogether there are eighteen root downfalls, which are explained in The Bodhisattvas' Grounds by Asanga and Compendium of Trainings by Shantideva. Although only eighteen are enumerated, each root downfall has many different aspects.
…(11) Explaining emptiness to those who are likely to misunderstand - We incur a root downfall if we teach emptiness in an unskilful way and cause those who are listening to develop serious and harmful misunderstandings.
...(15) Speaking falsely about profound emptiness If we lack a correct understanding of emptiness, and yet teach emptiness to others claiming with a selfish motivation that we have a direct realization of emptiness, we incur a root downfall.[1]

[1] “The Bodhisattva Vow,” Geshe Kelsang Gyatso, Tharpa Publications, 1995, Page 27 - 32