  Let $\pi$ be a set of primes. We say that a finite group $G$ is a
$\mathcal{D}_\pi$-group if the maximal $\pi$-subgroups of $G$ are conjugate. In
this paper, we give an affirmative answer to Problem 17.44(b) from "Kourovka
notebook", namely we prove that in a $\mathcal{D}_\pi$-group an overgroup of a
$\pi$-Hall subgroup is always a $\mathcal{D}_\pi$-group.
