I'd say the top two are direct and definitely impolite. Number two may seem polite to a direct sort of person, but the blame makes it impolite. Of the latter three I'd say the top one is not only the most concise and direct, but also fairly polite. These last two are more polite, but lack directness.
"You made a mistake here and need to correct it."
"Please correct this mistake."
"There's a mistake here that needs correcting."
"Can you correct this mistake?"
I'd say the top two are direct and definitely impolite. Number two may seem polite to a direct sort of person, but the blame makes it impolite. Of the latter three I'd say the top one is not only the most concise and direct, but also fairly polite. These last two are more polite, but lack directness.