In Windows and Active Directory, there is one system responsible for making access decisions in nearly *all* cases: the Security Reference Monitor. This system makes access decisions by analyzing security descriptors on securable objects and User Rights Assignments:
In "Azure", the story is very, very different. There are multiple forms of access control, and multiple services responsible for making access decisions.
"Azure" means the 600+ distinct services that comprise Microsoft's cloud computing platform.
Understanding who has control of any given object in any given Azure service requires a complete understanding of *all* of these systems and how they cooperate with one another.
Whether you're an attacker or defender, I will explain and demonstrate in my @nullcon talk how graphs bring accurate and clear understanding of effective permissions in Azure.
New abuse primitives that take advantage of legitimate administrative protocols and features are wildly exciting. Why? Because no object is an island. Everything is interconnected, and that interconnectedness can have enormous impact. Thread: 🧵
You may or may not be familiar with the childrens' book, "If You Give a Mouse a Cookie:"
It's a classic children's moral illustrating the slippery slope idea:
If you give a mouse a cookie, it will ask for a glass of milk.
But it's too hard to drink the milk, so now the mouse wants a straw.
The mouse is worried it has a milk mustache, so now it wants a mirror.
In the upcoming #BloodHound 4.1 release, we are introducing 3 new edges. Let me explain why this is actually more impactful than it may sound: 🧵
Let's say you have a basic graph with 3 nodes all connected to each other (this is called a Strongly Connected Graph). We'll call these nodes 1, 2 and 3:
How many possible paths are there? We can determine that by searching through non-cyclic trees originating from each node. For example, if we start at 1, we can visit 2 then 3, or 3 then 2:
I’m a firm believer in the (cliche) adage, “Outcomes, not output.” It’s not about the number of lines of code you wrote in 2021, but the impact those lines of code had - the outcomes they created. Here’s 5 small things you can do in 2022 to create big AD security outcomes:
#1: Audit the owners of your domain controller computer objects. Update the owner of each object to the Domain Admins group for that domain.
Time required: up to 1 hour
Potential attack path impact: extremely high.
Risk of breaking something: very low
#2: Use BloodHound to find where Domain Users/Everyone/Auth Users has privileged access, and remove all such instances.
Time required: up to 1 week
Potential attack path impact: extremely high.
Risk of breaking something: low
Enough time has passed now that we are starting to see the outcomes of this methodology, which I'd like to talk to you about:
Strip away the brands, the tools, the people, and everything else, and you are left with the only thing that REALLY matters:
The problem.
The problem that APM seeks to solve is the persistent availability and reliability of attack paths.
Pentesters, red teamers, and real attackers have been abusing attack paths, specifically in Active Directory, for over 20 years. AD attack paths are INSANELY reliable. They can be abused with reliable tools, including legitimate admin tools like Powershell and PsExec.
This service is accessible to every VM in Azure. As far as I know, there's no reason to ever disable this service for a VM, so it should always be accessible to every Azure VM.
IMDS's REST API is available to each VM at the non-routable, local IP of 169.254.169.254.
Lina is writing the technical content our industry needs: deeply technical, clearly explained, and appropriate for both offense and defense audiences. See her writings here: inversecos.com