The point is that if you crack it, they should send you to some unique link. Even if it's not super hard, it at least proved some level of technical competency and do should allow you to prioritised interview access (maybe at least skipping initial screening).
Not everyone is working on awesome stuff at an intelligence agency. They still need people to work on their 20 year old hellscape of an ERP system in hated language(java,ada,cobol, etc).
sure, but how much of the actual job will be solving puzzles? Seems unlikely to be representative of the work so the people who enjoy the actual work might begrudge the interview and the people who enjoy the interview might not enjoy the work.
I assume the solutions to these can be found publicly pretty quickly. So your secret bypass first filter loses utility after the first couple of people.
The reason you put this riddles online is to get to know people who love this kind of challenge. This is still the case if the solutions are available online, even though I would include a plead into my job ad not to post solutions online for fairness with respect to other potential applicants who mananged to solve the riddle.
When in a job interview, it should be very easy to find out whether the person found the solution online or he "cheated"; simple ask some detailed questions how the person came up with this and that part of the approach.
Perhaps filtering out the people who can neither solve it nor Google it is enough of a filter by itself. Not suggesting it should bypass more than initial screening, naturally.
