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Challenges while managing administrative privileges on your Azure AD joined Windows 10 devices

By default, on Windows 10 devices which are Azure AD joined, the user performing the join is added to the Local Administrator group. Besides the user and the local administrator (which is disabled by default), two other SIDs are added without any friendly name which explain who they are. So where are those SIDs coming from?

It is possible to make the user a normal user while enrolling the device, but then you have to create a Deployment Profile and use Windows Autopilot. See: Configure Autopilot profiles or use Bulk enrollment. See: Bulk enrollment for Windows devices

Note: This post reflects the status of Azure AD local administrative privileges as of February 11th 2020. Functionality may change, even right after this post has been published.

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Did you already modify your Azure AD consent defaults settings? Here is why you should

As you may know, it’s possible for your users to sign-in to SaaS based applications using their Azure AD account. By doing this, a Single Sign On (SSO) experience is created for the user. Before this SSO for an SaaS based application is possible though, the user needs to accept (a) permission request(s) from the application allowing the application to access the users data on its users behalf, even when the user is not using the application.

Added February 11th: Erik Loef pointed me to the following two interesting articles detailing on how oAuth can be used to exploit Office 365 environments. See:

Shining a Light on OAuth Abuse with PwnAuth
Introducing the Office 365 Attack Toolkit

TL;DR; – Disable user app consent, and enable admin consent requests as soon as possible!

Note: This post reflects the status of Admin consent as of February 9th 2020. Functionality may change, even right after this post has been published.

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Microsoft deprecates Conditional Access baseline policies in favour of Security Defaults, here is what you need to know and do

Last week, Microsoft announced that the Azure AD conditional access baseline policies will not make it out of their current preview status. The functionality of the baseline policies will be made in available in a new feature called “Security Defaults”, Microsoft will remove the baseline policies on February 29th, so if you are using them you need to take action in order to make sure to keep their functionality in place. Here is what you need to know.

I’ve discussed the baseline policies in part 5 of my blogpost series “Conditional Access Demystified“, while they provided a welcome addition, one of the main disadvantages of the baseline policies in its current preview form was that there was no option to exclude accounts from the policy, which was in contradiction with the best practice for break glass accounts and therefore made the policies not usable in some scenario’s.

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Report-only mode, and some more handy reporting functionality for Conditional Access and Azure AD

During its annual Microsoft Ignite 2019 conference this week, Microsoft announced a new feature for Conditional Access called Report-Only mode in preview.

So, what is Report-only mode?

Report-Only mode is a new option within a Conditional Access policy. Besides the option to turn the conditional access policy on or off, the option to Report-only has been added.

New Report-only option
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Extending Conditional Access to Microsoft Cloud App Security using Conditional Access App Control

In my blog article series on Conditional Access Demystied I mentioned that Conditional Access can be used to route sessions toward Microsoft Cloud App Security (MCAS). In this article I will go into more detail on what MCAS is, and how to setup Conditional Access App Control.

Disclaimer: This article discusses the full option MCAS product, there are some other flavors providing partial functionality like Office 365 Cloud App Security and Cloud App Discovery (CAD). For information about licensing, see the Microsoft Cloud App Security licensing datasheet.

What is Microsoft Cloud App Security (MCAS)?

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Conditional Access demystified, part 8: Resources and further references

This article is the last part of a series, for which the following articles are available:

Conditional Access demystified, part 1: Introduction
Conditional Access demystified, part 2: What is Conditional Access?
Conditional Access demystified, part 3: How does Conditional Access work?
Conditional Access demystified, part 4: Designing a Conditional Access strategy
Conditional Access demystified, part 5: Implementing Conditional Access
Conditional Access demystified, part 6: Troubleshooting Conditional Access
Conditional Access demystified, part 7: Modifying Conditional Access to suit your special needs

In the last part of this series I will summarize some of the sources I used for writing this series of articles.

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Conditional Access demystified, part 7: Modifying Conditional Access to suit your special needs

This article is part 7 of a series, for which the following articles are available:

Conditional Access demystified, part 1: Introduction
Conditional Access demystified, part 2: What is Conditional Access?
Conditional Access demystified, part 3: How does Conditional Access work?
Conditional Access demystified, part 4: Designing a Conditional Access strategy
Conditional Access demystified, part 5: Implementing Conditional Access
Conditional Access demystified, part 6: Troubleshooting Conditional Access
Conditional Access demystified, part 8: Resources and further references

When you want to integrate other products into your Conditional Access environment you can use “Custom controls” to include products from other vendors into your Conditional Access conditions. If a custom control is used the browser is redirected to the external service, performs any required authentication or validation activities, and is then redirected back to Azure Active Directory. If the user was successfully authenticated or validated, the user continues in the Conditional Access flow. More information and some samples can be found here: Azure AD + 3rd party MFA = Azure AD Custom Controls – https://blogs.technet.microsoft.com/cbernier/2017/10/16/azure-ad-3rd-party-mfa-azure-ad-custom-controls/. This feature is still in preview but very promising for 3rd party vendors who want to integrate with Conditional Access.

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Conditional Access demystified, part 6: Troubleshooting Conditional Access

This article is part 6 of a series, for which the following articles are available:

Conditional Access demystified, part 1: Introduction
Conditional Access demystified, part 2: What is Conditional Access?
Conditional Access demystified, part 3: How does Conditional Access work?
Conditional Access demystified, part 4: Designing a Conditional Access strategy
Conditional Access demystified, part 5: Implementing Conditional Access
Conditional Access demystified, part 7: Modifying Conditional Access to suit your special needs
Conditional Access demystified, part 8: Resources and further references

In this part of the series we will go into more detail on where we can find information which can help us to troubleshoot Conditional Access policies.

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Conditional Access demystified, part 5: Implementing Conditional Access

This article is part 5 of a series, for which the following articles are available:

Conditional Access demystified, part 1: Introduction
Conditional Access demystified, part 2: What is Conditional Access?
Conditional Access demystified, part 3: How does Conditional Access work?
Conditional Access demystified, part 4: Designing a Conditional Access strategy
Conditional Access demystified, part 6: Troubleshooting Conditional Access
Conditional Access demystified, part 7: Modifying Conditional Access to suit your special needs
Conditional Access demystified, part 8: Resources and further references

Before you start implementing your Conditional Access policies you should define an implementation strategy, some things to consider are:

  1. Make sure that Modern Authentication is enabled for Exchange Online (EXO) and Skype for Business Online (SfBO), SharePoint online has modern authentication enabled out of the box
  2. Create 2 break glass accounts, these accounts, which are global administrator should have complex passwords and will be excluded from any conditional access policy created and must have MFA disabled (or either one of two per account). More information about creating break glass accounts can be found here: Manage emergency access accounts in Azure AD – https://docs.microsoft.com/en-us/azure/active-directory/users-groups-roles/directory-emergency-access. Also keep in mind that you might want to change the default account settings for the Break Glass accounts using PowerShell: https://docs.microsoft.com/en-us/azure/security/azure-ad-secure-steps#step-2—reduce-your-attack-surface
  3. For each conditional access policy created, we will create an exclusion group, so that we can deal with exceptions in our environment. These exception groups will be setup with Access review functionality (if available) to make sure that the membership of these groups are evaluated on a regular basis.
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Conditional Access demystified, part 4: Designing a Conditional Access strategy

This article is part 4 of a series, for which the following articles are available:

Conditional Access demystified, part 1: Introduction
Conditional Access demystified, part 2: What is Conditional Access?
Conditional Access demystified, part 3: How does Conditional Access work?
Conditional Access demystified, part 5: Implementing Conditional Access
Conditional Access demystified, part 6: Troubleshooting Conditional Access
Conditional Access demystified, part 7: Modifying Conditional Access to suit your special needs
Conditional Access demystified, part 8: Resources and further references

When designing a Conditional Access strategy for a customer we first need to start with an inventory of the environment, in the most ideal situation you would design and implement conditional access in a green field scenario, but I for sure never had that luxury before so it’s better to assume that the customer is already using cloud apps and wants to implement conditional access as an security measure.

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