Passwords alone aren’t enough anymore. Phishing, credential stuffing, and password reuse attacks are rampant, and a single stolen password can open the door to your entire tenant. Multi-Factor Authentication (MFA) adds a critical extra layer, blocking over 99% of credential-based attacks. Making MFA universal ensures attackers can’t rely on the weakest link.
Stolen passwords = instant access: Attackers can compromise accounts with no challenge.
Tenant-wide risk: One breached account can be used to spread malware or steal data.
Compliance failure: Many regulations mandate MFA as a baseline control.
Go to Entra ID Admin Center.
Navigate: Security > Conditional Access.
Create a new policy:
Assignments: Target all users.
Cloud apps: Select all apps.
Access controls: Require Multi-Factor Authentication.
Exclude only break-glass accounts (secured with long, complex passwords and monitored closely).
Enable and enforce the policy.
Partial rollout: If MFA isn’t required for all apps, attackers will find the unprotected ones.
Over reliance on SMS: Text-based MFA can still be phished or SIM-swapped—push or app-based methods are stronger.
Forgotten service accounts: Some scripts or legacy apps can break when MFA is enforced; these should be updated or isolated.
Promote stronger MFA methods
Encourage users to use authenticator apps or FIDO2 keys instead of SMS codes.
Enable MFA registration policy
Require users to register methods during onboarding to avoid gaps.
Audit MFA coverage
Check Entra ID > Sign-in logs to ensure MFA challenges are being applied consistently.
Pair with Conditional Access for risky sign-ins
Add risk-based controls to challenge unusual login attempts more aggressively.
Implementing MFA for all users is one of the simplest and most effective defenses against modern attacks. With a single policy, you shut down credential-based threats before they begin. Universal MFA isn’t optional anymore, it's the baseline for any secure tenant.