We present a stochastic description of multiple scattering of polarized waves in the regime of forward scattering. In this regime, if the source is polarized, polarization survives along a few transport mean free paths, making it possible to measure an outgoing polarization distribution. We solve the direct problem using compound Poisson processes on the rotation group SO(3) and non-commutative harmonic analysis. The obtained solution generalizes previous works in multiple scattering theory and is used to design an algorithm solving the inverse problem of estimating the scattering properties of the medium from the observations. This technique applies to thin disordered layers, spatially fluctuating media and multiple scattering systems and is based on the polarization but not on the signal amplitude. We suggest that it can be used as a non invasive testing method.