From The Intercept:

“Both [pilots] appear to be influenced by pro-IS elements including extremist online propaganda by well-known radical Indonesia outlets and a suspected Indonesian foreign terrorist fighter who is likely to be in either Syria or Iraq,” the report states.

“Pilots, air crew and others with access to and within the aviation environment can pose obvious threats if these persons are radicalized. Their access and knowledge of security and safety regimes provides the ability to attempt attacks as witnessed by past global events,” warns the report, which also notes that a recent issue of Inspire, the magazine published by Al Qaeda in the Arabian Peninsula, encouraged attacks by those involved in aviation.