Cyber
Shared Trust Failure
Many healthy applications fail together. Was each one broken?
More healthy consumers are exposed for as long as the shared anchor stays trusted.
DEMONSTRATION SCENARIO
This is a demonstration scenario. It is not a live demonstration and does not report an executed result.
The situation
Several applications have been healthy. They rely on one shared signing or verification anchor.
Many of those applications fail together. Each one still looks locally sound.
Why this is hard
Applications can fail together because each was compromised, or because they share one bad anchor. Rebooting each application does not replace the anchor.
Treating every consumer as its own compromise should not count as the repair.
What the operator can see
- NormalApps healthy
- VisibleThey fail together
- At riskThe next tenant
What V8Y must determine
V8Y must distinguish one bad shared anchor from a separate compromise of each application, and say which further consumers are exposed either way.
What may happen next
More healthy consumers are exposed if the anchor stays in place.
What counts as recovery
Not recovery
Success is not a restarted application.
Recovery
Success is that the bad token class is rejected and good tokens still work.
Observed results
No executed results are published for this thread.
What this evaluation would test
- Many consumers, one possible anchor.
- A shared anchor and separate breaks kept apart.
- Good tokens preserved if the anchor is what changes.
- How a key was acquired is outside this demonstration.
These are the conditions the evaluation would test. They are not reported results.
Operational basis
View operational basis and sources
Derived from the summer 2023 Microsoft Exchange Online intrusion, in which one consumer signing key was accepted for enterprise mail across organizations. This demonstration does not establish how that key was acquired.
CISA Cyber Safety Review Board. Summer 2023 Microsoft Exchange Online intrusion review. 2023.
Discuss evaluating this situation
Does your environment face a similar problem?
The request keeps this mission and thread. It is not a claim that the demonstration has been validated in your environment.
The printable flyer is being revised and is not available for download.