TL;DR: Three MCP misconceptions are distorting how teams secure agent-based systems: MCP servers are usually local to one client, they are executable code with inherited privileges, and sandboxing does not remove indirect influence risk, according to Pynt. The core issue is trust boundary collapse, because MCP security depends on how servers are installed, isolated, and allowed to affect client decisions.
NHIMG editorial — based on content published by Pynt: Demystifying MCP (Model Context Protocol): 3 Common Misconceptions
By the numbers:
- Only 18% of MCP server deployments implement any form of access scoping for tool permissions.
Questions worth separating out
Q: How should security teams govern MCP servers used by AI coding assistants?
A: Treat MCP servers as privileged trust boundaries, not simple data sources.
Q: What breaks when MCP tools are exposed through one shared server?
A: Shared exposure collapses role separation.
Q: How do sandboxed MCP servers still create security risk?
A: Sandboxing blocks some direct access paths, but it does not stop a server from shaping the client's next action or influencing other servers through shared orchestration.
Practitioner guidance
- Classify every MCP server by authority, not by function Separate servers that only return data from servers that can execute code, invoke tools, or touch host resources.
- Define client-level trust boundaries for multi-server sessions Document which server combinations are allowed to coexist in the same client workflow, especially when one server may process untrusted data and another can access sensitive information.
- Verify provenance before local installation Require signed distribution, package integrity checks, and explicit source review for MCP servers before they are allowed to run on endpoints or developer hosts.
What's in the full article
Pynt's full article covers the operational detail this post intentionally leaves for the source:
- The specific MCP client and server interaction pattern shown in the demo, including how indirect influence led to sensitive data retrieval.
- The security reasoning behind local execution, inherited permissions, and why those properties change the trust model for AI-connected tools.
- The article's practical guidance on segregating privileged servers from untrusted sources and reviewing server trustworthiness over time.
- The concrete examples used to illustrate how sandboxed servers can still shape client behaviour through shared orchestration.
👉 Read Pynt's analysis of MCP misconceptions and server trust boundaries →
MCP server trust boundaries: what security teams are missing?
Explore further
MCP security fails when teams mistake protocol connectivity for trust containment. MCP is not merely a transport layer between a client and tools. It introduces a new trust surface where local execution, client mediation, and tool chaining become security-relevant in their own right. Teams that model it like a standard API boundary will miss where privilege is actually exercised, and that is how tool-connected identity risks accumulate.
A few things that frame the scale:
- 98% of companies plan to deploy even more AI agents within the next 12 months, despite documented rogue behaviour in 80% of current deployments, according to AI Agents: The New Attack Surface report.
- Only 52% of companies can track and audit the data their AI agents access, leaving 48% with a complete blind spot for compliance and breach investigation.
A question worth separating out:
Q: What should teams do before allowing multiple MCP servers in one workflow?
A: They should assess whether the workflow mixes untrusted data sources with privileged tool access, then separate those roles wherever possible. If co-location is unavoidable, the client should enforce strict routing rules so one server cannot trigger actions in another high-trust context.
👉 Read our full editorial: MCP security misconceptions are creating avoidable trust gaps