File distribution is becoming a key technology, in particular in large scale content broadcasting systems like DVB-H/SH. They largely rely on Application Level FEC codes (AL-FEC) in order to recover from transmission erasures. We believe that sooner or later, content integrity and source authentication security services will be required in these systems. In order to save the client terminal resources, which can be a handheld autonomous device, we have designed a hybrid system that merges the AL-FEC decoding and content integrity/source authentication services. More precisely our system can detect a random object corruption triggered by a deliberate attack with a probability close to 100% almost for free in terms of computation overhead.