What is the ruling on someone who accepted perfume from another person while in a state of ihram, knowing that it is not permissible for him to use perfume?

It is not permissible for a pilgrim in the state of ihram to use perfume on his body or clothes, due to the Prophet's (peace and blessings be upon him) saying concerning the pilgrim in ihram who died: "Wash him with water and sidr, and shroud him in two garments, and do not perfume him… for Allah will resurrect him on the Day of Resurrection, reciting the talbiyah." (Narrated by Al-Bukhari and Muslim). And his (peace and blessings be upon him) saying: "And do not wear anything that has been touched by saffron or wars." (Narrated by Al-Bukhari and Muslim).

Scholars have unanimously agreed on prohibiting a pilgrim in ihram from using perfume.

Whoever perfumes himself while in ihram out of courtesy must repent to Allah and is liable for a fidyah: either sacrificing a sheep, or feeding six needy persons, or fasting for three days.