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Answer: To enhance MFA in Microsoft 365, use Conditional Access and phishing-resistant authentication, protect privileged administrator accounts, enable Number Matching for Microsoft Authenticator, block legacy authentication, and monitor sign-in activity regularly.
As you know, passwords alone are no longer enough to protect digital accounts today. In Microsoft 365 Multifactor authentication MFA (also known as two-factor authentication, or 2FA) adds an important layer of protection to user accounts. During sign-in, it requires two or more different verification factors to confirm the real user identity. For secure login with MFA, user may put:
- A password, PIN, or security question and answer.
- Biometric verification, such as a fingerprint scan or facial recognition.
- A physical hardware security key (like a YubiKey), a push notification in a smartphone, or time-based one-time passcode (TOTP) via authenticator app.
However, even after enabling MFA alone in Microsoft 365, there is high risk of unauthorized account access. Attackers can target with phishing, MFA fatigue, stolen credentials, and other identity-based attacks. In this guide, we’ll discuss why enhancing MFA is necessary, how you can enhance MFA in Microsoft 265 along with data security.
Why Should You Enhance MFA in Microsoft 365?
MFA prevents an attacker from accessing an account with only a stolen password, but the level of protection depends on the authentication method you use.
For example, SMS codes and approval notifications provide useful protection, but attackers can still use phishing or social engineering to trap users. MFA fatigue attacks can also send repeated approval requests until a user accidentally accepts one.
For such reasons, your Microsoft 365 security should move beyond simply turning on MFA. A stronger approach combines MFA with authentication policies that control who can sign in, how they authenticate the real identity, what device they use, and what resources they can access.
A wider range of SMEs and large tech-firms are now combining strong authentication methods with Conditional Access, phishing-resistant MFA, administrator protection, and are conducting regular monitoring to enhance Microsoft 365 tenant MFA.
Important: Over 600 million identity-based attacks and fraudulent sign-in attempts are reported every day. Since Microsoft is committed to provide highest security, multifactor authentication (MFA) can block more than 99.9% of account compromise attacks.
How Can You Enhance Microsoft 365 Tenant MFA?
You can enhance Microsoft 365 tenant MFA by using phishing-resistant authentication, setting up Conditional Access, applying authentication strengths, enabling Number Matching, etc. The ways to strengthen MFA in Microsoft 365 are discussed in detail below:
Opt for Right MFA Approach for Your Microsoft 365 Tenant
Microsoft Entra ID provides two modern approaches to implement an MFA (Multi-factor Authentication) baseline for security Security Defaults and Conditional Access.
Security Defaults are useful when you want a simple security baseline with minimal configuration. On the other hand, Conditional Access is a more suitable security measure when you need policies such as:
- Require MFA for specific users or applications
- Require stronger authentication for administrators
- Block access from certain locations
- Require compliant devices
- Apply different rules based on sign-in risk
Note: Organizations prefer Condition Access over Security defaults as it offers more intrinsic and precise security measures. Also, it helps to manage bulk users and admins.
Use Phishing-Resistant MFA
To enhance the security of your Microsoft 365 tenant, you must move towards phishing-resistant authentication. With stronger mechanisms, phishing-resistant methods make it much harder for attackers to get or reuse authentication credentials. Microsoft supports several phishing-resistant options that include:
- Passkeys
- FIDO2 security keys
- Windows Hello for Business
- Certificate-based authentication
Use Authentication Strengths
Microsoft Entra authentication strengths allow administrators to specify what type of authentication users must provide. The built-in options include:
- Multifactor authentication strength
- Passwordless MFA strength
- Phishing-resistant MFA strength
For example, you can create a Conditional Access policy that requires administrators to use phishing-resistant authentication rather than allowing SMS or other weaker methods.
Protect Microsoft 365 Admins First
You must provide stronger protection to Admin accounts because they have access to sensitive tenant settings and data than ordinary user accounts. So, start by identifying authorized positions such as:
- Global Admin
- Security Admin
- Exchange Admin
- SharePoint Admin
- User Admin
Keep Microsoft Authenticator Number Matching Enabled
With the Microsoft Authenticator number matching system, you can enter the number displayed during the sign-in attempt instead of simply tapping Approve. This makes it harder for attackers to exploit MFA fatigue by repeatedly sending unexpected approval requests.
However, Number Matching should not be confused with phishing-resistant MFA. Number Matching is applicable for accounts that require stronger protection.
Block Legacy Authentication
If legacy authentication remains enabled with your account, an attacker may attempt to use an old protocol to bypass some of the protections applied to modern sign-ins. So, block that, and before blocking it, check that no users or applications still depend on legacy protocols. A process to block legacy authentication is:
- Review Microsoft Entra sign-in logs
- Identify legacy authentication attempts
- Find the users and applications responsible
- Migrate supported applications to modern authentication
- Set up Conditional Access policy to block legacy authentication
- Monitor sign-ins after the policy is enabled
Combine MFA With Conditional Access
MFA (Multi-factor Authentication) becomes more effective when it works with other access controls. You must prefer using MFA combined with conditional access. Conditional Access can consider signals such as user or group, application, location, device status, user risk, sign-in risk, authentication strength, etc.
Create Emergency Access Accounts
You may know that strong security policies can sometimes cause an unexpected problem. Admins can lock themselves out or fail to access due to outages, misconfigurations, or cyberattacks. To mitigate this risk, maintain emergency access, or emergency accounts (break-glass accounts). These accounts should:
- Be used only for emergencies
- Have strong credentials
- Be monitored carefully
- Be tested periodically
- Not be used for everyday administration
Plan for MFA Recovery
MFA security also depends on what happens when a user loses access to an authentication method.
Common situations, like a phone got lost or stolen, bought a new phone, deleted an Authenticator account, lost a passkey (FIDO2), replaced a security key, etc, the access to the account becomes complex.
So, create a clear recovery process before enforcing stronger MFA. Microsoft Entra Temporary Access Pass (TAP) can also help users register passwordless authentication methods securely. Your help desk should verify a user’s identity before resetting authentication methods. Otherwise, an attacker who has stolen a password could try to convince support staff to remove or replace the victim’s MFA method.
Monitor MFA After Deployment
An MFA policy should not be considered successful simply because it has been enabled. Regular monitoring is also good practice to stay aware. It helps to identify authentication problems and suspicious activity that are occurring and what they may impact later. So, review Microsoft Entra activity as mentioned below and determine that your MFA policies are actually carrying out the expected protection:
- Failed authentication attempts
- Repeated MFA prompts
- Risky sign-ins by users and admins
- Unexpected admin activity
- Legacy authentication attempts
- Conditional Access failures
MFA is Crucial for Microsoft 365 Security: What About Data Security
MFA protects access to your Microsoft 365 accounts, but it does not protect against every type of security or data-loss scenario. For a wider identity, access, device, and data-protection strategy, follow Microsoft 365 security best practices.
If your organization needs to back up Office 365 data, maintain an appropriate backup and recovery strategy. There are several native ways, like eDiscovery or exporting PST via Outlook, but you can opt for another alternative: Kernel Export Office 365 to PST for an easier and direct Office 365 backup.
With it, you can backup specific data, prevent duplicate data, and avoid unnecessary hassle with protected sign in. However, these activities serve a different purpose from MFA: MFA protects account access, while backup and export processes help preserve recoverable copies of data.
Conclusion
Now that you have an idea about the risk of cyber-attacks and login attempts daily. Also, you are now familiar with MFA in Microsoft 365. To enhance Microsoft 365 tenant MFA, don’t stop at simply requiring users to complete an MFA prompt.
Start with a suitable MFA baseline, then strengthen it with Conditional Access, authentication strengths, phishing-resistant methods, administrator protection, Number Matching, legacy-authentication blocking. Even after that, consider a continuous monitoring approach and continue to improve protection on a regular basis. For your data security besides any issue, cyber-attack, or login restriction, get your data in local storage as backup with export Office 365 to PST tool and recover when you need.
Frequently Asked Questions
Ans: Yes. Admin accounts should use stronger authentication requirements because compromising an admin account can affect the entire Microsoft 365 tenant.
Ans: Security Defaults are suitable for organizations that need a simple security baseline while Conditional Access is better when you need detailed control over users, applications, devices, locations, risks, and authentication methods.
Ans: No. MFA protects account access from unauthorized login attempts. It does not replace a separate Microsoft 365 backup and recovery strategy.
