I'm going to list all of the pilgrims associated with the church, and explain for each one if he/she is corrupt:
The Prioress: the head of the monastery. She is polite, and very neat. She is also described as being quite sentimental, but there is no specific mention of her being sinful. It should be noted that she is quite rich, however, which is a violation of her vows.
The Nun: not described.
The Priest: not described
The Friar: described in much detail. Although very "merry", he is greedy and corrupt. He takes money for people in order to "forgive" their sins, but then pockets the money for himself.
The Monk: not really corrupt, but he spends his time not attending to his vows. Instead, he attends to the needs of the Prioress and to his own pleasures.
The Parson: a pastor in the church, who is true to his faith and his vows. Unfortunately, this makes him very poor.
The Summoner: an agent of the Church courts whose job it is to bring sinners before the court. However, he will take their money as a bribe to not report their sins.
The Pardoner: also takes money to "forgive" people. Besides this, he passes off junk as "relics" from Rome.
As you can see, Chaucer clearly paints the church as corrupt and greedy, and not at all concerned with religious vows and faith (save for the few).