In the not so recent past ,the full service airlines ruled the skies in India and there was no outsourcing of department functions,every body was on company payroll.
The most important fact is that security was never outsourced as a government policy every airline "Full service or LCC" had to have the security department on its pay role, they could out source the world but not Aviation Security, however with the emergence of LCC some departments have been outsourced like baggage handlers/cabin cleaning/ drivers.
If we talk of threats we have one sitting right here in front of us, outsourced workers at the airport, for an outsourcing company the airline is just a "business header" and nothing else the loyalty factor does not exist in there thinking and for the LCC it is a win win situation the less business heads they have on board the less the headaches they have, however in doing so they compromise on the basic tenant's of security.
There have been cases of contract workers walking away with baggage or stealing from the baggage it is easy for them to get hand in glove with an outsider who wants to cause some damage. A company employee will think twice before he takes the same step.