Microsoft 365 is a prime target for attackers. Here are five warning signs that your tenant configuration needs a security review before a breach occurs.
M365 Is a High-Value Target
Microsoft 365 holds your email, files, calendars, and collaboration data — making it one of the most valuable targets for cybercriminals. Many small businesses set up M365 and assume the default protections are enough. They rarely are.
Warning Signs to Watch For
First, you have legacy authentication protocols still enabled. Older protocols like POP3, IMAP, and basic authentication bypass modern protections and are frequently exploited. Second, MFA is not enforced for every user, including admins. Third, external sharing is broadly allowed without restrictions, exposing sensitive files.
Fourth, you see frequent phishing emails reaching inboxes despite built-in filtering. Fifth, admin activity is not logged or reviewed. Without audit logging, you cannot detect unauthorized changes to accounts, mail rules, or permissions.
What a Review Should Cover
A proper M365 security review examines identity settings, conditional access policies, data loss prevention rules, sharing configurations, email security settings, and audit logging. It should also verify that alerts are configured for high-risk events like privilege escalation or mass file downloads.
Take Action
If any of these warning signs apply to your business, schedule a review soon. Many M365 security improvements can be implemented quickly and make a dramatic difference in your resilience against phishing, account takeover, and data theft.