Yes, there's a long history of thefts
at cryptocurrency exchanges and wallets, dating back to the infamous
robbery of Tokyo - based Mt. Gox in 2014.
Currently
cryptocurrencies like Bitcoin, Ethereum, Litecoin, etc. are traded
at large
exchanges, which follow the traditional logic of centralization, with a single point of failure for corruption, information - theft, fraud, coercion,
robbery, and so on.