Context : Aims : To understand planet formation it is necessary to study the birth environment of planetary systems . Resolved imaging of young planet forming disks allows us to study this environment in great detail and find signs of planet-disk interaction , as well as disk evolution . In the present study we aim to investigate the circumstellar environment of the spectroscopic binary T Tauri star CS Cha . From unresolved mid- to far-infrared photometry it is predicted that CS Cha hosts a disk with a large cavity . In addition , SED modeling suggests significant dust settling , pointing towards an evolved disk that may show signs of ongoing or completed planet formation . Methods : We observed CS Cha with the high contrast imager VLT/SPHERE in polarimetric differential imaging mode to resolve the circumbinary disk in near infrared scattered light . These observations were followed-up by VLT/NACO L-band observations and complemented by archival VLT/NACO K-band and HST/WFPC2 I-band data . Results : We resolve the compact circumbinary disk around CS Cha for the first time in scattered light . We find a smooth , low inclination disk with an outer radius of \sim 55 au ( at 165 pc ) . We do not detect the inner cavity but find an upper limit for the cavity size of \sim 15 au . Furthermore , we find a faint co-moving companion with a projected separation of 210 au from the central binary outside of the circumbinary disk . The companion is detected in polarized light and shows an extreme degree of polarization ( 13.7 \pm 0.4 % in J-band ) . The companion ’ s J- and H-band magnitudes are compatible with masses of a few M _ { \mathrm { Jup } } . However , K- , L- and I-band data draw this conclusion into question . We explore with radiative transfer modeling whether an unresolved circum-companion disk can be responsible for the high polarization and complex photometry . We find that the set of observations is best explained by a heavily extincted low mass ( \sim 20 \mathrm { M } _ { \mathrm { Jup } } ) brown dwarf or high mass planet with an unresolved disk and dust envelope . Conclusions :