After receiving a lot of great feedback on my post 5 Things To Check In Your Microsoft 365 Tenant, I thought I’d do another post, picking my top 5 items from the Center for Internet Security’s (CIS) benchmark Microsoft Intune for Windows 11 Benchmark v3.0.1
This is a really big list to pick from, much bigger than the Microsoft 365 one – the document is over 1000 pages! Also you may look at this list and say ‘What has this got to do with Intune, I can apply these settings to any Windows 11 PC?’ – This is true, but the options CIS has laid out are ones that are natively available in Intune and therefore easily deployable. I’m also going to spend more time explaining the meaning behind the setting rather than telling you how to do it, as the CIS documentation (again freely avaialable for non-commerical use) clearly explains the setting and how to configure it.
Again these 5 things are important and I’ve tried to pick items that aren’t in the secure state by default, so I hope you find something new (or at least reassured!).
1. Ensure ‘Turn off access to the Store’ is set to ‘Enabled’
By default, any Windows 11 PC has the Microsoft Store enabled, the app installed, and a user can use it to obtain any software available in the store. I’ll avoid the whole ‘are Microsoft Store apps safe’ as I’m not privy to Microsoft’s application monitoring regime, just like Google’s Google Play or Apple’s App Store – but just like blocking users from installing software from other sources and methods, the Microsoft Store should be controlled in a corporate environment. There’s an entire history behind the Microsoft Store for Business and Microsoft Store for Education which is being replaced by packaging the apps in Intune for Microsoft Store which is still a work in progress with original retirement planned for 2023 being postponed.
All this leads to this one setting, which is just preventing the user being prompted the Windows Store as an option to find a program to open a file or protocol that currently has no association (for example, a user found a data.db file and tries to open it). They’ll see this dialog:
Either enable the confusingly named Intune setting ‘Turn off access to the Store’ (due to it only doing the below, which it describes in the details of the setting) or use this registry setting to remove the Microsoft Store option for any ‘open with’ dialog – Turn off access to the Store (admx.help)
Simple, but it ticks the box of a user complaining that they just followed what the computer told them to do when they end up with some wacky or weird solution obtained from the Microsoft Store that they start entering company data into. It also ties into a bigger piece around how you handle the Microsoft Store as a whole. I also found this blog post which goes into great detail about the Microsoft Store and how to control it, including the above setting: Restricting or blocking access to the Microsoft Store (call4cloud.nl)
2. Ensure ‘Backup Directory’ is set to ‘Backup the password to Azure AD only’
LAPS (Local Administrator Password Solution) is an incredibly important solution to prevent lateral movement between devices. At the high level, it is designed to automatically manage the local administrator password on each device, and make it unique. This means if someone was able to obtain the password on a single device, they can’t then use that same account against every other device in an organisation. More details: https://learn.microsoft.com/en-us/windows-server/identity/laps/laps-overview (and back in 2017 I was going on about it too https://www.adamfowlerit.com/2017/02/havent-deployed-laps-yet/)
Up until October 2023, this was only an on-premises natively supported solution; but now Intune supports it too. If you haven’t looked into LAPS or didn’t realise you could now do it in a cloud only environment, then put it at the top of your list.
Assuming you are now living with LAPS, the option Backup Directory controls where the LAPS password for each device goes. Apart from the default disabled option, this can either be ‘Backup the password to Active Directory only’ or ‘Backup the password to Azure AD only’ (yes I know it’s now Entra ID, nobody’s updated this name yet).
If you’re cloud only (Entra ID Joined) or cloud first, then this option should be ‘Backup the password to Azure AD only’ – your Entra ID should be more secure than your Active Directory, and this decision should really be a part of whatever system you’re putting first. It’s also a bit neater to view/report on events where any account is looking at the LAPS password value of a device in Entra ID, compared to on-premises Active Directory where you may have many different AD domain controllers and hopefully good monitoring/reporting of events across the entire environment – but more room for error there.
Creating a policy for this is quite a simple process from the Microsoft Intune Admin Center:
3. Ensure ‘Allow Cross Device Clipboard’ is set to ‘Block’
I am a huge fan of Clipboard in Windows and use it many times every single day. If you aren’t aware of this feature, press Winkey + V on your keyboard and it’ll pop up, asking if you want to enable it. It keeps a history of your clipboard contents – whatever you Ctrl + X or right click > copy. This is really handy when you’re copying all the time, but want to paste/recall anything beyond the absolute last thing you copied. It supports both text and pictures. Of course, this means it will copy things like passwords and other data you probably don’t want floating around. One feature of Clipboard in Windows is the ability to enable ‘Clipboard history across your devices’ which sounds somewhat handy, but drastically increases the risk of data leakage when you’re syncing that information to your account (if a work account, then should sit securely in your M365 tenant/Entra ID) or Microsoft consumer account. It’s just an unnecessary risk for little benefit – the clipboard history should stay local and be cleared on logoff/reboot. It will purely sit in memory and be lost afterwards when Clipboard sync is disabled.
Please start or keep using Clipboard in Windows but turn off Clipboard sync. It’s enabled by default.
Here’s the registry setting: Allow Clipboard synchronization across devices (admx.help)
4. Ensure ‘Notify Unsafe App’ is set to ‘Enabled’
Another setting disabled by default. Instead of explaining, I’ll just quote directly from the Group Policy setting:
This policy setting determines whether Enhanced Phishing Protection in Microsoft Defender SmartScreen warns your users if they type their work or school passwords in Notepad, Winword, or M365 Office apps like OneNote, Word, Excel, etc.
If you enable this policy setting, Enhanced Phishing Protection in Microsoft Defender SmartScreen warns your users if they store their password in text editor apps.
If you disable or don’t configure this policy setting, Enhanced Phishing Protection in Microsoft Defender SmartScreen will not warn users if they store their password in text editor apps.
This one sounds pretty reasonable right? If a user types their password into a program being monitored by Enhanced Phishing Protection, it’ll pop up and tell you:
Note that with my testing, this doesn’t apply to Microsoft Edge, nor does it apply if you paste your password, it has to be typed – but still a pretty good user reminder on something they shouldn’t be doing!
Interestingly I couldn’t find the registry value on GetADMX but the ‘Notify Unsafe App’ setting is available in Group Policy, and in Intune – create a Settings catalog policy, and use the settings listed under the category SmartScreen > Enhanced Phishing Protection: Notify Unsafe App. Further information here: https://learn.microsoft.com/en-us/windows/security/operating-system-security/virus-and-threat-protection/microsoft-defender-smartscreen/enhanced-phishing-protection?tabs=intune
Also worth calling out checking out the other Enhanced Phishing Protection settings at the same time: Automatic Data Collection, Service Enabled, Notify Malicious. Notify Password Reuse.
5. Ensure ‘Turn off toast notifications on the lock screen (User)’ is set to ‘Enabled’
This final one is pretty obvious. When a PC is locked, you don’t want notifications popping up that may contain sensitive information and be visible by anyone that can see the screen. This is a feature that I don’t think should even exist… but it does and it’s on by default. You want to enable the setting to disable the feature (yes this is a dig at the inconsistent state of settings and enabling/disabling!).
Easily done via Turn off toast notifications on the lock screen (admx.help) or enable the Turn off toast notifications on the lock screen via Intune via a Configuration Profile. A full guide is available here: Disable Toast Notifications From Lock Screen Using Intune HTMD Blog (anoopcnair.com)
That’s it for the list – as always I hope you found it interesting and love hearing any feedback (including constructive criticism), and hope it helps people out there to always be thinking security.