Lying and insulting are Haraam in any condition, but these are inhibited especially in the state of Ihram, it means these are from the act of which a Muhrim should renounce in performing them. It is an obligatory precaution to abstain from expressing the superiority of himself/herself to others or expressing the weakness of others against himself/herself, and these three acts have been collected in the term “Fosuq” according to some Hadees quoted from the infallibles (a.s.) in the holy verse;
فَلا رَفَثَ وَ لا فُسُوقَ وَ لا جِدالَ فى الْحَجّ
Let there be no obscenity, nor wickedness, nor wrangling in the Hajj. (2:197)
Thus whenever a Muhrim perform these acts, he/she has done wrong but the Ihram is not invalidated, and the atonement of that is Istighfar (asking forgiveness from Allah). It is better than a person abstain from saying anything bad, evil and incompatible to the soul of Hajj and say nothing other than good words.