specterops.iowriteup

Pass-the-Passkey Family of Attacks

SpecterOps research introduces "Pass-the-Passkey," a family of 20+ attack techniques against passkey/WebAuthn authentication, including three zero-days: Windows 11 logging complete WebAuthn assertions to an Event Log readable by unprivileged users (patched July 2026), Microsoft Entra ID historically failing to enforce WebAuthn anti-replay protections (challenge reuse, session binding, signature counters), and local malware that calls the native Windows WebAuthn API directly to phish users with a convincing native-looking passkey prompt. The write-up argues these implementation failures mirror classic credential-relay attacks like Pass-the-Hash and NTLM Relay, and recommends device-bound passkeys with attestation enforcement for high-value accounts.