Is it permissible to lie to avoid envy and harm? And is there such a thing as a "lie of benefit"?

Lying is not permissible in such situations due to the lack of necessity. One can avoid embarrassment through alluding and dissimulation (tawriya). Explicit lying is forbidden except out of necessity, urgent need, or a considerable benefit that cannot be attained otherwise. A Muslim should abandon that which does not concern him.