Conn. Gen. Stat. § 53a-60: Assault in the second degree: Class D or C felony.

(a) A person is guilty of assault in the second degree when: (1) With intent to cause serious physical injury to another person, the actor causes such injury to such person or to a third person; or (2) with intent to cause physical injury to another person, the actor causes such injury to such person or to a third person by means of a deadly weapon or a dangerous instrument other than by means of the discharge of a firearm; or (3) the actor recklessly causes serious physical injury to another person by means of a deadly weapon or a dangerous instrument; or (4) for a purpose other than lawful medical or therapeutic treatment, the actor intentionally causes stupor, unconsciousness or other physical impairment or injury to another person by administering to such person, without his consent, a drug, substance or preparation capable of producing the same; or (5) the actor is a parolee from a correctional institution and with intent to cause physical injury to an employee or member of the Board of Pardons and Paroles, the actor causes physical injury to such employee or member; or (6) with intent to cause serious physical injury to another person by rendering such other person unconscious, and without provocation by such other person, the actor causes such injury to such other person by striking such other person on the head; or (7) with intent to cause physical injury to another person, the actor causes such injury to such person by striking or kicking such person in the head while such person is in a lying position.

(b) Assault in the second degree is a class D felony or, if the offense resulted in serious physical injury, a class C felony.