Whispers of Infinity + Corrupting Fever no cost life

if I use Whispers of Infinity and Corrupting Fever or other cost life skill(no use Lifetap Support)

It cost is become 0.

So i can use 6-link Corrupting Fever and no cost until I change Corrupting Fever's cost (like change Corrupting Fever's link)

A similar bug applies to March of the Legion. The ES cost is only the added cost from the blessing, the base cost is ignored. So it costs 278 ES when it costs 1k+ mana.