The short answer: why AI assistants in Microsoft 365 reach so much
AI assistants in Microsoft 365 can reach everything the people behind them can reach, including files that were shared too widely years ago. That exposure is not new. What is new is that it now answers questions.
- People build agents in Microsoft 365 that run at their own access
- Audit exposure, remediation and a stalled AI program are the costs
- Good means an inventory, approval before exposure and continuous review
People across the business are building AI agents in Microsoft 365
People across the business are building AI agents, in Microsoft 365, without going through IT. Each one runs at the access of whoever built it.
That access was granted for a person doing a job, not for a standing capability that answers anyone who asks it. Nobody approved it for this purpose, because nobody was asked.
When the person who built an agent changes team or leaves, the agent keeps running. Gartner expects the average Fortune 500 enterprise to be running more than 150,000 agents by 2028, up from fewer than 15 in 2025.
Three costs, in the order they usually arrive
Audit exposure
Under the EU AI Act, regulators now ask what AI systems the organization runs, what they reach, and who approved them. Those questions are answerable or they are not.
Remediation
Fixing access across thousands of workspaces after an incident typically costs more than finding it beforehand, and it lands on the team least able to absorb it.
A stalled AI program
When nobody can say what an agent reaches, the safe answer to every rollout request is no, and the investment stalls while the risk stays.
AI agent governance checklist the approver can hold you to
- A complete inventory. Every agent and connected app, with a named owner and a plain statement of what data it can reach.
- Approval before exposure. One check between an agent being built and an agent being shared, light enough that people still build.
- Continuous review. With the evidence produced on demand instead of assembled for each audit.
What a breach involving AI costs
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USD 6 million
average cost of a breach where AI was involved in the attack, against USD 4.99 million overall
IBM Cost of a Data Breach Report 2026
Specialist Risk Group grew from 119 staff to 450 through acquisition, each one bringing its own accounts and data into the same Microsoft 365 estate. Their infrastructure lead described the problem before they fixed it:
There is no way to view it in one place in a simple contextual way.
Frequently asked questions
Why can AI assistants reach so much?
What does it cost to leave agents ungoverned?
What does good AI agent governance look like?
How do I make the case for AI agent governance internally?
How does Rencore Governance help?
Where this fits in Rencore Governance
AI & Agents module
One inventory of every Copilot Studio agent and every site that holds SharePoint agents, with owner, reach and policy.
See the AI & Agents moduleCopilot and agent governance
Find agents without an owner, see what each one can reach and enforce policies on a schedule.
See Copilot governanceEU AI Act evidence for agents
Per-agent evidence for risk classification and audits, produced on demand.
See the solution