Add URL warning to all emails

[Graham1968]

At work here - after being hit with several phishing attempts...a couple of which were successful - the IT manager would like to add a warning to all emails that have a URL embedded in them, whether they originate from outside the organization or not.

Is there any way to do this in O365.  We have already configured O365 to add a warning to emails that originate outside our domain, but I don't see anything in the mail transport rules that specifically allows you to configure warnings in the email has a URL in it.

Is this possible and what do I need to do to make it happen?  Is there a PowerShell command that will do what the Exchange Admin Center won't?

[#2]

Hello, you should have a look at Safe links https://docs.microsoft.com/en-us/microsoft-365/security/office-365-security/safe-links?view=o365-wor...

Also see this article about EXO tagging https://office365itpros.com/2021/03/11/exchange-online-external-email-tagging/

[#3]

Safe links are your best bet here. In case you dont have the appropriate license to use them, you can try creating a Mail flow rule with a regex condition to detect any URLs in the body/subject of email, but that wont stop users from clicking them :)

[#4]

@Graham1968 

Thanks both of you....I think you've pointed me in the right direction.  I'll need to dig a bit deeper on this to figure out how to configure it.