As Microsoft pushes passkeys as the passwordless future, enterprises are discovering a critical blind spot: Conditional Access policies don’t evaluate passkey authentication the same way they evaluate traditional MFA. This gap is creating a false sense of security for many organizations that believe they’re fully protected under Zero Trust principles.
The Passkey Promise vs. Reality
Passkeys are undeniably more secure than passwords. They’re phishing-resistant, encrypted, and tied to your device. Microsoft has been aggressively positioning them as the foundation of modern identity security. However, the implementation in Entra ID has a significant limitation: Conditional Access policies cannot directly see or restrict passkey sign-ins in the same granular way they can with traditional MFA methods.
When a user signs in with a passkey, Conditional Access still functions, but the signal chain is incomplete. You can see the sign-in event, but you cannot create policies that specifically require passkey authentication over other methods, nor can you apply different policy conditions specifically to passkey flows. This creates a scenario where attackers could potentially bypass your carefully crafted access policies.
The Hidden Risk in Your Zero Trust Architecture
Organizations implementing Zero Trust with passkeys are making an incorrect assumption: that passkey authentication is automatically aligned with their Conditional Access requirements. It isn’t. If an attacker compromises a user’s device or gains access through a secondary authentication method, Conditional Access policies may not catch the anomaly if the user hasn’t yet migrated to passkey-only authentication.
The real danger emerges in hybrid environments where some users are on passkeys and others still use password + MFA. This creates inconsistent policy enforcement and a two-tier security posture that undermines Zero Trust principles.
Practical Solutions for Enterprises
First, audit your Conditional Access policies immediately to identify gaps between your intended Zero Trust model and your actual policy coverage. Second, implement device-based Conditional Access rules as a compensating control to restrict sign-ins from non-compliant or unapproved devices, regardless of the authentication method used. Third, consider using Azure AD Premium P2 for risk-based conditional access to catch anomalous sign-in patterns that passkey authentication alone won’t prevent.
Most importantly, establish clear communication with your security and identity teams about the current limitations of passkeys in Entra ID and plan a phased migration strategy that doesn’t assume passkeys are a complete replacement for your current Conditional Access framework.
Ready to optimize your Entra ID security posture? Simplicity IT specializes in designing Zero Trust architectures that properly integrate passkeys, Conditional Access, and device compliance. Schedule a consultation to review your current identity and access strategy.