We compute the master integrals for massless two-loop vertex graphs with three off-shell legs. These master integrals are relevant for the QCD corrections to H→V*V* (where V = W, Z) and for two-loop studies of the triple gluon (and quark-gluon) vertex. We employ the differential equation technique to provide series expansions in epsilon for the various master integrals. The results are analytic and contain a new class of two-dimensional harmonic polylogarithms.