What action should be taken if Microsoft Defender for Identity flags a security issue with user accounts authenticating with clear-text passwords?

Choosing to enforce password complexity requirements and require password changes is the most appropriate action when Microsoft Defender for Identity flags a security issue with user accounts authenticating with clear-text passwords. This step directly addresses the vulnerability associated with clear-text password usage.

By enforcing password complexity requirements, organizations can ensure that passwords are not only more difficult to guess or brute-force but also promote the use of stronger passwords that can help mitigate risk. Additionally, requiring users to change their passwords immediately prevents any potential exploitation that could arise from the clear-text passwords that have been flagged. Since the primary issue here is the clear-text transmission of passwords, taking action to enhance password security is a proactive measure in improving overall security posture.

The other options, while beneficial in various contexts, do not directly address the immediate risk posed by clear-text password authentication. Reviewing network perimeter defenses can help in securing the broader network but does not mitigate the specific issue of weak password usage. Conducting educational sessions on safe internet practices can raise awareness but does not provide an immediate solution to the flagged issue. Similarly, encrypting all network traffic is a valuable security measure but may not be viable or necessary to implement immediately and does not resolve the specific concern related to authentication practices.