The ongoing replacement of monolithic system designs with Off-The-Shelf approaches aims to enable the loosely coupled integration of heterogeneous existing legacy systems. This trend is currently promoting a new architectural paradigm, called System of Systems (SoS). An SoS is made of independent and autonomous constituent systems (CSs) which interact to achieve higher level goals also with the intervention of humans. While enhancing the services provided, an SoS at the same time introduces new challenges to be faced, specifically when dependability and security properties must be addressed. In fact, traditional failure and attack detection approaches are not easily applicable to an SoS due to the autonomy, dynamicity and the uncoordinated evolution of its CSs. This paper first analyses the challenges posed by SoS for the development of effective failure and intrusion detectors; then it investigates which are the available solutions for SoS in the state of the art. Finally, a possible approach that is currently under development is envisioned together with the planned case study.