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Apr 03 2024, 07:00 AM - 11:00 AM (PDT)
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Office operations missing username

Brass Contributor

We get the odd alert through for rare office operations that doesn't seem to have any information on the user or mailbox the operation was performed on.

 

I suspect this may be because the user or mailbox in question has been deactivated but I cannot be sure. We have other logs showing the usernames properly.

 

Here is a sample of an Add-MailboxPermission command that demonstrates this (data has been scrubbed):

[
{
"Name": "Identity",
"Value": "mailbox the permissions will allow access to"
},
{
"Name": "User",
"Value": "<Organisation Exchange Id>\\$001ABC-D12EF3GH4I56" - this normally shows a username
},
{
"Name": "AccessRights",
"Value": "FullAccess"
},
{
"Name": "InheritanceType",
"Value": "All"
}
]

 

Does anyone know what this $001ABC-D12EF3GH4I56 parameter is called and how I could map it to an actual user? I cannot seem to find a matching string in Exchange properties.

1 Reply

I've managed to figure this out. A fresh set of eyes will do you good for any problem. :stareyes:

 

It's the samaccountname it seems which you can find via Exchange powershell.

 

 

Get-Mailbox -Identity username@domain.com | fl

 

 

Running this command to search by SamAccountName will output the user. This didn't work for me initially because I was using double quotes but you need to use single quotes to stop the dollar sign from being expanded into a variable https://stackoverflow.com/questions/17452401/escaping-dollar-signs-in-powershell-path-is-not-working

 

get-mailbox -resultsize unlimited | where-object {$_.SamAccountName -eq '$1ABCD0-EFGH23456'}

 

 

I'm thinking now there could be a way to leverage some of the steps in this blog article to automatically link this attribute to a username via Exchange 365. 

https://techcommunity.microsoft.com/t5/azure-sentinel/enriching-azure-sentinel-with-azure-ad-informa...

 

What you will see as well if you expand the Office Activity logs is that there will often be a similar event logged just before or just after which will have the actual username in it anyway.