Skip to main content

The new Mail.ReadBasic permission for the Microsoft Graph API and how to put it to use

Microsoft have just released the Mail.ReadBasic permission into beta for the Microsoft Graph endpoint https://developer.microsoft.com/en-us/graph/blogs/new-basic-read-access-to-a-users-mailbox/ which is a much needed addition that allows the creation of automation and apps that can just access messages at a more meta information level without having access to the Body or Attachments. Privacy and security are always pressing issues especially around email so this can turn down the privacy concerns while also reduce the security concerns of giving full access to content. 

Lets look at one use case for this new permission which is getting the Message Headers from a Message that has arrived in a users Mailbox that you suspect might be spam but you want the header information to do some analysis. Normally if you wanted to build an app to automate this you would have to at least assign Mail.Read which would give full access to all email content in a Mailbox (either delegated or every mailbox in a tenant in the case of Application permissions). This new grant allows us to just to get the Meta information like TO/From and all the first class properties which now includes the InternetMessageHeaders https://docs.microsoft.com/en-us/graph/api/resources/internetmessageheader?view=graph-rest-1.0

All you need to get going with using this is an application registration with just the Mail.ReadBasic permission assigned (for delegate access you would also need access to their underlying Exchange Folder or Mailbox your going to be querying via the normal Exchange DACL mechanisms).

I've put together a simple script that uses the ADAL for authentication and you can then search for a message based on the Internet MessageId and it will retrieve and then process the antipsam headers so you can look at DKIM,SPF and DMAC information just with this permission grant.


An example of this in use say if we are looking at the last 60 minutes of our trace logs for messages that where FilteredAsSpam (meaning the message ended up in the Junk Mail folder in the Mailbox)


We can take that MessageId and feed it the script cmdlet and get



A few things that are missing for this at the moment are to be really useful it needs to be an Application permission which I believe is coming. The other thing is you really need to be able to enumerate the Folder Name which this restricted at the moment and the ItemClass should be a first class property as you need it to determine the different types of emails you might be detail with.

Popular posts from this blog

The MailboxConcurrency limit and using Batching in the Microsoft Graph API

If your getting an error such as Application is over its MailboxConcurrency limit while using the Microsoft Graph API this post may help you understand why. Background   The Mailbox  concurrency limit when your using the Graph API is 4 as per https://docs.microsoft.com/en-us/graph/throttling#outlook-service-limits . This is evaluated for each app ID and mailbox combination so this means you can have different apps running under the same credentials and the poor behavior of one won't cause the other to be throttled. If you compared that to EWS you could have up to 27 concurrent connections but they are shared across all apps on a first come first served basis. Batching Batching in the Graph API is a way of combining multiple requests into a single HTTP request. Batching in the Exchange Mail API's EWS and MAPI has been around for a long time and its common, for email Apps to process large numbers of smaller items for a variety of reasons.  Batching in the Gr...

EWS-FAI Module for browsing and updating Exchange Folder Associated Items from PowerShell

Folder Associated Items are hidden Items in Exchange Mailbox folders that are commonly used to hold configuration settings for various Mailbox Clients and services that use Mailboxes. Some common examples of FAI's are Categories,OWA Signatures and WorkHours there is some more detailed documentation in the https://msdn.microsoft.com/en-us/library/cc463899(v=exchg.80).aspx protocol document. In EWS these configuration items can be accessed via the UserConfiguration operation https://msdn.microsoft.com/en-us/library/office/dd899439(v=exchg.150).aspx which will give you access to either the RoamingDictionary, XMLStream or BinaryStream data properties that holds the configuration depending on what type of FAI data is being stored. I've written a number of scripts over the years that target particular FAI's (eg this one that reads the workhours  http://gsexdev.blogspot.com.au/2015/11/finding-timezone-being-used-in-mailbox.html is a good example ) but I didn't have a gene...

Sending a MimeMessage via the Microsoft Graph using the Graph SDK, MimeKit and MSAL

One of the new features added to the Microsoft Graph recently was the ability to create and send Mime Messages (you have been able to get Message as Mime for a while). This is useful in a number of different scenarios especially when trying to create a Message with inline Images which has historically been hard to do with both the Graph and EWS (if you don't use MIME). It also opens up using SMIME for encryption and a more easy migration path for sending using SMTP in some apps. MimeKit is a great open source library for parsing and creating MIME messages so it offers a really easy solution for tackling this issue. The current documentation on Send message via MIME lacks any real sample so I've put together a quick console app that use MSAL, MIME kit and the Graph SDK to send a Message via MIME. As the current Graph SDK also doesn't support sending via MIME either there is a workaround for this in the future my guess is this will be supported.
All sample scripts and source code is provided by for illustrative purposes only. All examples are untested in different environments and therefore, I cannot guarantee or imply reliability, serviceability, or function of these programs.

All code contained herein is provided to you "AS IS" without any warranties of any kind. The implied warranties of non-infringement, merchantability and fitness for a particular purpose are expressly disclaimed.