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Imagine if one could simply use FIDO Security Keys or Security Cards on any device through a unified interface that works seamlessly. When examining pluggable interfaces, we find various types such as USB-A, USB-C, and Thunderbolt, which often limit cross-device usability or require adapters. Maybe devices don’t have a pluggable interface at all due to design decisions, security restrictions or something similar. In theory there is one interface that appears to be a promising solution: NFC....

Summary I discovered a vulnerability in Envoy Gateway, which allowed attackers to manipulate access logs via malicious User-Agent string. By injecting payloads into the User-Agent Header, attackers could overwrite log fields (e.g., spoof IP addresses) or crash observability tools by corrupting log formats. After discovering this CVE-2025-25294, I responsibly disclosed it to the maintainers and also fixed the code via that Commit. Impact In all Envoy Gateway versions prior to 1....

TL;DR Companies rely solely on Passkeys for authentication. Issues and breaking changes within the Passkey ecosystem can prevent users from signing in. We kindly request all contributors of the Passkey ecosystem to be mindful of your responsibilities and act carefully. More details Companies rely solely on Passkeys for authentication Some global companies have progressed beyond the adoption phase and now rely solely on Passkeys. In fact, they have chosen to discard other conventional authentication methods (i....

Conference Talk at Authenticate Conference 2023: How to Go Passwordless Without Fallback. You can see the recording here

Conference Talk at European Identity and Cloud Conference 2023: Enforce a faster sign-in with Biometrics and Pin – even for legacy apps of a DAX company. You can see the recording here

TL;DR We want to enforce FIDO-only to achieve phishing resistant authentication without the possibility of downgrade attacks. But many web-views in legacy applications do not support WebAuthn. Use case: How to enforce FIDO-only even if your users use mobile apps or desktop applications that contain legacy WebViews to render the authentication flow? We call it “Detached FIDO Authentication”: Provide the option to jump out of applications that use legacy WebViews (do not support WebAuthn) into the Operating System Standard Browser....

Conference Talk at Authenticate Conference 2022: Our journey to implement FIDO in a global science & technology company. You can see the recording here

Keynote at Authenticate Virtual Summit: Modernizing Healthcare with Strong Authentication: Moving Beyond Passwords. You can see the recording here