Supposedly nobody, not even the CIA nor the NSA has been able to crack the last passage.
https://en.m.wikipedia.org/wiki/Kryptos
https://www.businessinsider.com/a-secret-message-hidden-in-a-cia-sculpture-25-years-ago-might-finally-be-solved-2014-11
https://math.ucsd.edu/~crypto/Projects/KarlWang/index2.html
