What is the ruling on using cosmetics made from pork fat out of ignorance, and are they forbidden?

It is impermissible to use or sell products proven to contain pig fat or any substance derived from it due to their impurity. The prohibition requires certainty or strong presumption of this, not mere rumors. There is no sin upon one who uses them out of ignorance. The components of these substances are known through reliable experts, or through widespread knowledge and renown. Piety and caution are required in these matters.