Multi-factor Authentication (MFA) and Conditional Access (CA) policies are powerful tools to protect Azure AD users’ identities.
For instance, one may allow access only from compliant devices and require MFA from all users.
However, because of Azure AD authentication platform architecture, users can bypass home tenant MFA and CA policies when logging in directly to resource tenants.
This blog post tries to shed some light on how Azure AD authentication works under-the-hood. We’ll introduce the issue, describe how to exploit it, show how to detect exploitation, and finally, how to prevent the exploitation.
The blog is co-authored with @SravanAkkaram and is based on his findings.
Devices (endpoints) are a crucial part of Microsoft’s Zero Trust concept. Devices can be Registered, Joined, or Hybrid Joined to Azure AD. Conditional Access uses the device information as one of the decisions criteria to allow or block access to services.
In this blog, I’ll explain what these different registration types are, what happens under-the-hood during the registration, and how to register devices with AADInternals v0.4.6.
In October 2020, someone contacted me and asked whether it would be possible to create BPRTs using AADInternals. I hadn’t even heard of BPRTs, but was eventually able to help him to create BPRTs. Now this functionality is included in AADInternals v0.4.5.
In this blog, I’ll explain what BPRTs are and how they can be used to join multiple devices to both Azure AD and Intune. I’ll also show the dark side of BPRTs: how they can be used to conduct DOS attacks against Azure AD, and how to detect and prevent this.
Azure Cloud Shell is a browser-based shell for managing Azure resources using your favourite shell, Bash or PowerShell. Cloud Shell is typically used from Azure Portal. It provides an easy access to Azure CLI, Azure PowerShell and Azure AD PowerShell.
In this blog, I’ll introduce a new way to access Cloud Shell from PowerShell (requires AADInternals v0.4.3 or newer).
In my previous blog I demonstrated how to create a Persistent Refresh Token (PRT) by joining imaginary device to Azure AD.
In this blog, with AADInternals v0.4.2, I’ll show how to make those devices compliant, allowing bypassing compliance related conditional access (CA) policies.
In this blog, I’ll report my own findings regarding to PRT and introduce the new functionality added to AADInternals v0.4.1.
Multi-factor Authentication (MFA) is nowadays a recommended method for providing extra protection for users. In most cases, it protects users from phishing attacks as the attackers can’t log in even they have user’s credentials.
In this blog, I’ll report my findings on how the Azure AD MFA works under-the-hood, and how I built a custom authenticator app for Android. I also introduce some methods how the rogue administrator can bypass MFA when using user’s compromised credentials.