Step 1. Find code on GitHub.

Step 2. Copy it into your repo. Who cares what the license says, how would the authors of that code ever see it being misused, because the place it is being misused requires a security clearance?

Step 3. Deliver the code as yours.

Truly, how will the people who authored something on GitHub ever know? Any circumstance you describe would require someone without clearance to know implementation details of some software. Which is to say, either the thing I describe happens all the time, or security clearances are overblown.