What is true about misconfiguration as one of the most challenging types of cyber threats?

All the above

Erroneous permission$-$level attribution on cloud services and networked backups exposed sensitive data through weak or non$-$existent authentication.

Incidents where attackers gain access to vulnerable systems left exposed by inexperienced administrators or users $($e$.$g$.,$ default factory settings$)$

Options $\text{'}A\text{'}$ and $\text{'}C\text{'}$ Only

Employees and insiders falling for phishing emails that resulted in account takeover or access to sensitive data.