It's interesting to me that you'd go the hassle of hosting your own SharePoint on prem, but leave it internet facing. I would have assumed a the Venn diagram of these organizations to be entirely contained in orgs forcing you to use a VPN.
What a pity that CISA has been purged down of effective useful people and turned into another sad selected-for-political-compliance-only force.
Arizona recently got attacked from Iranian hackers & didn't even bother trying to get help from CISA. https://archive.is/2025.07.19-143305/https://www.azcentral.c...
CISA is so so vital. Investigating incredibly wide ranging attacks like this, or the Salt Typhoon attack are vital for this nation. But the show is being run by a bunch of people who value political dogma far above anything else. https://www.techdirt.com/tag/cisa/
So you don't do that. You use zero trust and don't care that things are exposed to the internet.
Working from anywhere (remote sites, home, your phone) is a huge benefit. Organizations want to control their data entirely while still wanting their organization to be able to access it.
With a VPN the attack surface of this vulnerability would have been miniscule compared to a publicly accessible zero-day RCE
(And it's not like you have to allow carte-blanche access behind the wall)
Defense in depth!
The other salient point is that all connections are established outbound through a broker, and importantly this is the case from both sides: The appliance at the terminating end of the tunnel establishes reverse tunnels to the broker for the connections, so it's never "exposed to the internet".
The broker can then push to your SIEM or whatever so you can have your SOC log jockeys harass your employees for accidentally leaving NordVPN on after watching international sports.
There are actual benefits: You can do things like allow logins to system A from anywhere, but system B only from your home country, you can do JIT network access requests, etc... but mostly it's vendor marketing to get you to spend too much money.
They can be implemented using a variety of technical patterns but they all share a common "each request is authenticated, encrypted" property instead of "anything goes once the tunnel is up" property.
And yet every customer of mine have some of their servers on a VPN. At the very least they enable ssh only on ports on the private network.
My way of mapping it to VPN mindset is "per app clientless VPNs straight to where the things are hosted". In an extremely open ruleset with all of the servers on a corporate network this could theoretically devolve into "a traditional clientless VPN to the office".
It doesn’t matter what network you are connecting from, but it does matter that you’re connecting from a company-issued laptop that’s in a trustworthy state.
The big difference is once you’re in, with a VPN you have direct access to the whole network.
With a zero trust setup, access has to be granted to you (or your ACL group) on a per-application basis. It makes it much harder for an attacker to move laterally when everything is default-deny.
- You must "VPN in" to access any corporate resources of any type, even ones on the corporate network when you're sourcing from the corporate network
- The client forms a separate "VPN connection" (can be clientless, but same concept) per app you access, rather than assuming a single parent VPN server can get them to any resource
- Every default ruleset started with deny all and only specific allow rules were added over time
Then you've got enough to call it a zero trust implementation. You can also take things the other way, i.e. you could "deconfigure" a zero trust setup to look and function almost exactly as a normal corporate VPN tunnel.
Rather than go through this whole thread each time, people just refer to all of this as "zero trust networking".
In a pure implementation, the same level of trust is implied (absolutely none at all) whether a device is connecting to a resource from the public internet or the same subnet.
It's software your employer pre-installs on your work PC, that asks you to log in with your work SSO credentials, performs some endpoint security checks, then routes your traffic over a virtual network adapter, and thereby allows you to access workplace resources, even when working from home.
The main difference is it adds some semi-authenticated states. Correct device, username, password, and 2FA, but failed a device posture check because they plugged their phone into their laptop to charge it? The 'Zero Trust' system can block some systems, while letting them retain access to others.
The other big difference is the pricing - rather than paying a five-figure sum upfront for networking hardware, you instead pay $25 per employee per month, forever.
this is not a requirement of zero trust.
The NIST Zero Trust Architecture (ZTA) implementation guides (SP 1800-35) [2] cut through the nonsense and AI generated marketing smoke.
In ZTA, ALL network locations are untrusted. Network connections are created by a Policy Engine that creates and tears down tunnels to each resource dynamically using attribute-based-access-controls (ABAC). Per request.
Microsoft doesn’t have any products that can do full ZTA, so several pillars are missing from their “Zero Trust” marketing materials.
[1] https://www.microsoft.com/insidetrack/blog/securing-the-bord...
TBH several pillars are missing from their entire security posture.
It’s a symbiotic relationship that allows them to stop having to spend resources to compete in the market on merit.
What does it mean in technical terms? What kind of tunnels are whose and what is their purpose?
Basically a policy evaluation point (PEP) evaluates the security posture of both parties before and after a handshake, then creates a logical or physical path of some kind of between the actor and the resource. This can be done with software-defined virtual networks and stateful firewalls, at one or more of the OSI layers.
How is this PEP better?
Once upon a time Microsoft marketed it as, and a lot of Orgs adopted SharePoint as their Intranet. With SharePoint 2019 being sunset, a lot of Orgs are scrambling to implement replacements.
It likely will be entirely contained, at least in theory. Because is your IT and OT isolated? They should be, but man could I tell you something about the energy and public sectors... Let's just say, that if you're in an organisation with any sort of OT, then you may as well assume that everything you have is facing the internet in some way. I suspect it's frankly like this in any sort of enterprise organisation getting worse the more the org views IT purely as a cost center.
This is why we don't just rely on things like VPNs. Everything we have uses port security (mac-adresses) at a much more ganular level than the VPN does. At least for the parts of our systems landscape where this is possible. With something like SharePoint it's hard to allow specific devices because it's usually something everyone should have some sort of access to. Then you have all the organisations where SharePoint also has some sort of non-VPN access because some CEO level wanted it at one point since they can't be bothered to bring a work PC to their Holiday home.
I never remember thinking years ago how nice it would be to have all of our private docs that we only need to access on our private network accessible to the public. I just wasn’t thinking outside the box enough.