attack

noun | at·tack

1. : an attempt to prove something invalid or incorrect especially through judicial procedures made an attack on the will as not properly witnessed; specifically : an attempt to have the judgment of a court corrected or overruled : an attempt to have the judgment of a court corrected or overruled

   — collateral attack
   : an attack on a judgment made during or by a proceeding brought for a different purpose — see also habeas corpus ad subjiciendum at habeas corpus

   — direct attack
   : an attack on a judgment made in a proceeding (as an appeal) brought for the specific purpose of having the judgment corrected or overturned