What is the ruling on a fetus conceived by a wife from the sperm of a foreign man due to her husband's inability to procreate, and to whom is it attributed, and is it permissible to abort it?

What the woman did is a crime and one of the major sins, because it is in the meaning of adultery, even if it is not exactly that. She transgressed God's limits and betrayed her husband. The fetus is attributed to the woman's husband, based on the Prophet's (peace be upon him) saying: "The child is for the bed, and for the fornicator is the stone." If the husband is certain that the fetus is not his, then he should disavow it through li'an (oath of condemnation). As for abortion, it is not permissible except out of necessity, such as a danger to the mother's life.