'Shadow Brokers' Leak Raises Alarming Question: Was the N.S.A. Hacked?

'Shadow Brokers' Leak Raises Alarming Question: Was the N.S.A. Hacked?

By DAVID E. SANGER

Outside experts said the data contained what appeared to be genuine samples of the top-secret code used in the production of the N.S.A.'s custom-built malware.