  This work studies mode stability of an STU black hole with four pairwise
equal $\rm{U(1)}$ charges in four spacetime dimensions. We investigate bosonic
perturbations for probe fields of different spins through the transformation
technique devised by Whiting in 1989. Finally, we introduce connection
relations inspired by the work of ~Duzta\c{s} (2016) to prove the absence of
unstable modes that solve the torsion-modified Dirac equation appropriate for
this black hole background.
