ABA Law Practice Today has an excellent reminder that cybersecurity implicates multiple provisions of the Model Rules:
[The leading ethics opinion] eferences five of the Model Rules of Professional Conduct as the foundation of the opinion. These rules pertain to the duty of competence, the expectation of keeping clients reasonably informed, attorney-client confidentiality, and the responsibility of a managing or supervisory attorney to ensure a firm’s compliance with the Rules of Professional Conduct for both attorney and non-attorneys alike.
Source: The Ethical Obligation of Maintaining Reasonable Cybersecurity Measures | ABA Law Practice Today