Why is the present perfect conjugation of Venire different from othere -ire verbs?

I just noticed this and wonder if Venire is the only verb to use -uto instead of -ito in the present perfect. I thought it was because Venire is intransitive, but then I found that Fallire and Stupire were the same:

Venire:  essere + venuto/venuti
Fallire:  essere + fallito/falliti 
Stupire: essere  + stupito/stupiti



Thanks for your help,

Jack Korpi

Hi Jack, 

Thank for your question!

"Venire" is not the only verb that ends in "-uto". 

Other examples include:
"Vendere" (to sell) = Venduto
"Cadere" (to fall) = Caduto
"Sedere" (to sit) = Seduto

Let me know if you need further examples or info and I will be very happy to help :)