https://denniskniep.github.io/index.xml

Conference Talk at IT Summit by Heise 2025, togther with Alexander Schwarz Regaining digital sovereignty using the example of digital identities Digital identities are the key to digital sovereignty.

TL;DR; This post explains a phishing technique for FIDO cross‑device (hybrid) authentication.

TL;DR; I found a bypass for the recently fixed vulnerability, CVE-2024-9956, in Mobile Safari.

Conference Talk at MCTTP 2025 Topic: Secure your Identity In today’s digital landscape, robust identity management is crucial for ensuring security and efficiency for companies.

TL;DR; EDIT 19.09.2025: Microsoft fixed it for normal Entra tenants, but still possible for federated Entra tenants.

Imagine if one could simply use FIDO Security Keys or Security Cards on any device through a unified interface that works seamlessly.

Conference Talk at Rethink!

Summary I discovered a vulnerability in Envoy Gateway, which allowed attackers to manipulate access logs via malicious User-Agent string.

Conference Talk at Inside IAM 2025 How to go all-in on Passkeys How do you allow Passkeys exclusively for all users – with no fallback to Password, SMS, Call or App?

TL;DR Companies rely solely on Passkeys for authentication.

Conference Talk at Authenticate Conference 2023: How to Go Passwordless Without Fallback.

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.

TL;DR We want to enforce FIDO-only to achieve phishing resistant authentication without the possibility of downgrade attacks.

Conference Talk at Authenticate Conference 2022: Our journey to implement FIDO in a global science & technology company.

Keynote at Authenticate Virtual Summit: Modernizing Healthcare with Strong Authentication: Moving Beyond Passwords.