MFA and Conditional Access: What It Means for Your Organization
Multifactor authentication (MFA) asks for a second proof, beyond a password, before someone can sign in.
Multifactor authentication (MFA) asks for a second proof, beyond a password, before someone can sign in.
Conditional Access is Microsoft’s way of setting rules for when and how that happens in your Microsoft 365 environment: which people, which apps, which devices, from where, and with which sign-in methods. Together they are one of the first things a customer, an insurer, an assessor or a regulator will ask about. Not all MFA is equal, though. Text message codes and simple approval prompts can be phished. ALCON DTS can help you require MFA for every user and every app that signs in through Microsoft Entra ID, move administrators and high-risk users to phishing-resistant methods, shut off old sign-in paths and keep a tested emergency plan for when sign-in breaks.
MFA is a sign-in that needs two different kinds of proof. CISA explains the point simply: “With MFA enabled, if one factor, such as a password, becomes compromised, unauthorized users will be unable to access the account if they cannot also provide the second factor.”
Conditional Access is the policy layer in Microsoft Entra ID, the identity service behind Microsoft 365. Microsoft describes Conditional Access policies as “logical if then statements.” If the assignments (users, resources and conditions) are true, then the policy applies access controls. A simple example from Microsoft: if you are an administrator signing in to a Microsoft admin portal, then you must complete MFA.
With Conditional Access you can require MFA for everyone, require a stronger method for administrators, require a managed device before anyone opens sensitive apps, block sign-ins from places you never do business, and block old sign-in methods entirely.
It covers: which sign-in methods you allow, which people and apps must use MFA, how strong the method must be for administrators and sensitive access, blocking legacy sign-in, emergency access accounts, and how you review sign-in activity.
It is not:
If your staff sign in to email, files or business apps over the internet, MFA applies to you. It matters most when:
Quick check: does this apply to you?
If both are true, MFA very likely applies to you. If a law, contract or insurance policy names specific MFA requirements, confirm with your attorney or broker how those requirements apply.
| Area | What good looks like | Why it matters |
|---|---|---|
| MFA for everyone | Every user registered and required to use MFA | A stolen password alone is not enough |
| Stronger methods where it counts | Phishing-resistant MFA for administrators and high-risk access; number matching at minimum for everyone else | CISA calls phishing-resistant MFA the gold standard |
| Conditional Access baseline | Policies that require MFA for all users and administrators and block legacy authentication | Rules apply the same way every time |
| Legacy authentication blocked | Older mail and sign-in protocols turned off | Legacy protocols can bypass MFA |
| Emergency access accounts | Two or more cloud-only accounts, phishing-resistant methods, excluded from blocking policies, monitored and tested | You can still get in if sign-in breaks |
| Device and location rules | Managed, compliant devices required for sensitive apps; unusual locations reviewed | Limits where your data can be opened |
| Review and evidence | Sign-in logs reviewed, MFA registration reports kept, policy changes recorded | You can show the control works |
CISA ranks MFA methods from strongest to weakest:
NIST reaches a similar place. NIST SP 800-63B-4, published in July 2025, states that “Passwords are not phishing-resistant,” “Out-of-band authentication is not phishing-resistant,” and “OTP authentication is not phishing-resistant.” At authentication assurance level 2, verifiers “SHALL offer at least one phishing-resistant authentication option.” NIST writes these guidelines for federal agencies, but many organizations use them as a reference. NIST allows syncable authenticators, such as synced passkeys, at AAL2 under extra safeguards, but not at AAL3, which requires a non-exportable key.
In Microsoft Entra ID, a Conditional Access control called authentication strength lets you require specific methods. Microsoft’s built-in phishing-resistant strength allows FIDO2 security keys, certificate-based authentication (multifactor) and the sign-in built into supported managed computers.
Microsoft gives you two starting points:
Microsoft 365 also offers a baseline security mode in its admin center that bundles recommended settings. Two of those settings appear as Conditional Access policies: requiring phishing-resistant authentication for administrators and blocking legacy authentication.
Microsoft now requires MFA for its admin portals as well. It began enforcing MFA for its cloud, identity and device admin centers in October 2024 and for the Microsoft 365 admin center in February 2025, rolling out gradually across organizations. A second phase, starting October 1, 2025, extends MFA to command-line, scripting and API tools that make changes to cloud resources.
Legacy authentication means older clients and protocols, such as older mail protocols, that don’t support modern sign-in. Microsoft explains the risk: “Legacy authentication doesn’t support multifactor authentication. Even if you have a multifactor authentication policy enabled on your directory, an attacker can authenticate by using an older protocol and bypass multifactor authentication.” Microsoft also says that “more than 99 percent of password spray attacks use these legacy authentication protocols.”
Before you block it, find anything that still depends on it, such as an old scanner that sends email or a line-of-business app, and plan a replacement.
A break-glass or emergency access account is how you get back in if normal administrator sign-in fails, for example during an outage or if the only administrator leaves. Microsoft’s guidance includes:
Microsoft also notes that emergency access accounts must complete MFA to reach its admin portals, which is another reason to set them up with phishing-resistant methods now.
Cyber insurance applications and renewal forms commonly ask about MFA. Typical questions ask whether MFA is required for:
Some applications also ask which methods you use, whether any accounts are exempt, and whether you block legacy sign-in. The exact questions vary by insurer and by year. Answer only what is true today, keep evidence such as MFA registration reports and policy screenshots, and talk with your broker if a question does not fit how your organization works. See our guide to security questionnaires.
You keep the compliance decisions. We run the controls. You decide the rules, the exceptions and who approves them. ALCON DTS can help configure and run MFA and Conditional Access in your Microsoft 365 environment and keep the records that show it working.
| Need | What ALCON DTS provides |
|---|---|
| MFA for everyone | MFA and enrollment for every user, with help for staff who get stuck |
| Conditional Access | Sign-in rules based on user, device and location, plus sign-in and user risk where you have Microsoft Entra ID P2, set up in the directory you already run |
| Administrator protection | Least-privilege administrator roles, with admin access kept tight and reviewed |
| Joiners, movers and leavers | Access changes kept current so unused accounts and access do not sit open |
| Guests and vendors | Guest and vendor access reviewed as part of the same picture |
| Devices | Devices kept updated, protected and encrypted, so device rules have something to check |
| Monitoring | Alerts routed to a named owner. When an alert fires, ALCON DTS opens a ticket, contacts your named owner and works the issue with you until it is back under control. |
| Questionnaire answers | Answers that come from the live environment, covering MFA, encryption, backups, logging and admin access |
The exact controls depend on your ALCON DTS plan and any project work. ALCON DTS does not provide legal advice, does not certify compliance and does not sign attestations for you.
Not sure which accounts can still sign in with just a password? We will review MFA registration, Conditional Access, legacy sign-in and emergency access in your Microsoft 365 environment and show you what to fix first.
Last reviewed: September 30, 2026
This page is general information about multifactor authentication, Conditional Access and related rules, not legal advice for your situation.
Want to know which accounts could still be taken over with a stolen password? We will walk through MFA, sign-in rules, legacy authentication and emergency access with you and give you a clear plan for what to fix first.