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maester365 / maester

The core repository for the Maester module with helper cmdlets that will be called from the Pester tests.
https://maester.dev
MIT License
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MS.AAD.3.7 and MS.AAD.3.8 assume you're running Hybrid #194

Closed JonesMikael closed 4 months ago

JonesMikael commented 5 months ago

I have som suggestions on the following tests:

MS.AAD.3.7: Managed devices SHOULD be required for authentication.
MS.AAD.3.8: Managed Devices SHOULD be required to register MFA.

They assume you're running a Hybrid environment and that you tick both [v] Require device to be marked as compliant and [v] Require Microsoft Entra hybrid joined device. Many of our customers are moving away from Hybrid or at least moving their devices to Entra ID Joined so the [v] Require Microsoft Entra hybrid joined device is no longer required for them.

Maybe change the test to just require one of them if that's suitable for your environment?

Snozzberries commented 5 months ago

It is a thought I fought with a fair bit while transcribing the original rego to pester tests. If we deviate our tests too far from the CISA controls it causes an issue and as we aren't authoritative for them we don't want to mislead any users of Maester. So there is a thought of having like an -alternate that would add a warning that understanding of the intent of the control is necessary.

For MS.AAD.3.7 & MS.AAD.3.8 The logic should test for OR on the CA policy config, are you seeing a different outcome or would just prefer to avoid having a CA policy testing for a setting that isn't used?

JonesMikael commented 5 months ago

Thanks for clarifying. I totally agree that we should follow good official regulations/practices - makes our life so much easier when describing our setup. CISA Strong Authentication & Secure Registration - MS.AAD.3.7v1 states this so it's rather them who should change it :)

What I see in most deployments are customers in hybrid environments are moving to Entra ID Joined + Compliance policies in place to make sure the device is Compliant and that is what you want to require. When this in place, most customers leave all Group Policies behind or even delete them and simply don't care about on-prem joined devices. if you leave [v] Require Microsoft Entra hybrid joined device you risk that a perpetrator could join a rouge device to your on-prem Active Directory and be able to access your cloud environment through that.

Of course, I could simply change the test to suit our environment.

I think in general, an -alternate or -deviation would be a good idea that still marks the test as green and "Passed as deviation" for those few tests where it's common to have an alternate solution for some customers but still considered "secure". I'm sure there are other tests like it, for example MS.AAD.7.6: Activation of the Global Administrator role SHALL require approval. Where we do agree, in some organisations that is not practical if they are a one-man shop :)

merill commented 5 months ago

I suggest adding a parameter to the test along the lines of -SkipHybridJoinCheck

The default policy aligns with CISA and customers can always adjust them to their risk model. In this case it improves the security posture over what CISA have currently defined.

Snozzberries commented 4 months ago

Thanks for the suggestion @JonesMikael, this has been added. If an environment does not meet the CISA control definition, then it will fall back to testing the alternate configuration and still pass.