  In this work we investigate the far-UV to NIR shape of the dust attenuation
curve of a sample of IR selected dust obscured (U)LIRGs at z$\sim$2. The
spectral energy distributions (SEDs) are fitted with CIGALE, a
physically-motivated spectral synthesis model based on energy balance. Its
flexibility allows us to test a wide range of different analytical
prescriptions for the dust attenuation curve, including the well-known Calzetti
and Charlot & Fall curves, and modified versions of them. The attenuation
curves computed under the assumption of our reference double power-law model
are in very good agreement with those derived, in previous works, with
radiative transfer (RT) SED fitting. We investigate the position of our
galaxies in the IRX-$\beta$ diagram and find this to be consistent with grayer
slopes, on average, in the UV. We also find evidence for a flattening of the
attenuation curve in the NIR with respect to more classical Calzetti-like
recipes. This larger NIR attenuation yields larger derived stellar masses from
SED fitting, by a median factor of $\sim$ 1.4 and up to a factor $\sim$10 for
the most extreme cases. The star formation rate appears instead to be more
dependent on the total amount of attenuation in the galaxy. Our analysis
highlights the need for a flexible attenuation curve when reproducing the
physical properties of a large variety of objects.
