Phishing for Primary Refresh Tokens and Windows Hello keys
In Microsoft Entra ID (formerly Azure AD, in this blog referred to as “Azure AD”), there are different types of OAuth tokens. The most powerful token is a Primary Refresh Token, which is linked to a user’s device and can be used to sign in to any Entra ID connected application and web site. In phishing scenarios, especially those that abuse legit OAuth flows such as device code phishing, the resulting tokens are often less powerful tokens that are limited in scope or usage methods. In this blog, I will describe new techniques to phish directly for Primary Refresh Tokens, and in some scenarios also deploy passwordless credentials that comply with even the strictest MFA policies.