As a corollary to this question what would be your recommendations of safe options for people wanting to store a portion of their cash in case of the above event.
Thanks.
While anything is 'possible', if a bank had to close for a period of time due to a cyber attack it would remain solvent. A bank run of course typically cannot occur if a bank is closed and access is denied. But of course once the problem is over customers might get very nervous and then withdraw money en masse. In such a case we would expect the government to guarantee deposits, to prevent a run. Banks have very good security but a breach is possible. But due to multiple checks and back-ups, money is unlikely to be 'lost' in a breach, it would more likely be a 'denial-of-service' attack. Accounts are guaranteed to $100,000 by CDIC. Other than holding physical cash personally or in a bank safety deposit box, there is not a lot of options for actual cash here. One could look to 'cash' ETFs such as PSA but they also own bank deposits and other than diversifying their assets they could still get caught up in such an attack.