Top 10 MCP Security Risks (and How to Avoid Them)

🛡️ Why MCP Security Matters

Model Context Protocol (MCP) is fast becoming the connective tissue for agent-native applications — bridging LLMs like Claude and GPT with external tools and APIs. But early deployments are facing real-world breaches, misconfigurations, and even injection attacks. The recent article by Secure Micro rang the alarm bells for a lack of security in MCP servers. It's time to reflect on what else is going to prevent companies fully realising the benefits of MCP.

MCP gives agents superpowers. But without proper guardrails, it gives attackers a backdoor too.

Let’s break down the top 10 security risks we’re seeing in the wild.

⚠️ Top 10 Security Risks in MCP Deployments

1. Publicly Exposed MCP Servers

MCP servers shouldn’t be discoverable via Shodan — and yet, here we are.

Impact: Anyone on the internet can hit your endpoints.
Fix: Block all public network access. Whitelist internal traffic. Run behind an API gateway or VPN.

2. No Authentication Layer

By default, many MCP servers accept unauthenticated requests.

Impact: Anyone can act as anyone.
Fix: Require token-based authentication (OAuth2, signed JWT, or scoped bearer tokens).

3. Lack of Scoped Authorization

MCP spec doesn't define scopes — so most implementations skip them.

Impact: An agent can access everything once authenticated.
Fix: Define least-privilege scopes per agent and per function. Validate on every request.

4. Missing Audit Trails

You can’t debug what you don’t log.

Impact: No visibility into what your agents accessed or modified.
Fix: Log every agent interaction: request origin, scope used, action taken, and output.

5. Hardcoded Secrets in Repos

Seen in multiple GitHub MCP examples.

Impact: Anyone can extract your API keys, internal IPs, and DB credentials.
Fix: Use env vars or secret managers. Scan repos with tools like TruffleHog.

6. Injection Vulnerabilities

Anthropic’s reference SQLite server had a confirmed SQLi vector.

Impact: Prompt or toolchain manipulation.
Fix: Sanitize all inputs, including model responses. Apply classic web security practices to agent interfaces.

7. No Rate Limiting or Abuse Protection

MCP agents can be spammed — especially if open to external LLMs.

Impact: DoS attacks, LLM credit burn, function abuse.
Fix: Add rate limiting and request origin validation. Log anomalies.

8. Overprivileged Agents

Many teams let agents access everything “just to get it working.”

Impact: One bad prompt = full database dump.
Fix: Treat agents like untrusted interns. Limit their actions per use case.

9. No Identity Abstraction

Agents act on behalf of users — but how do you prove who initiated what?

Impact: No accountability, no delegation, no rollback.
Fix: Implement structured delegation. Use tokens that encode both agent and user identity.

10. Unsecured Agent-to-Agent Calls

Agents calling other agents via MCP is powerful — and dangerous.

Impact: Chain-of-trust attacks.
Fix: Use signed requests, verify token chains, and scope every hop in the chain.

Tags:
#MCP #AgentSecurity #Authentication #Authorization #AIInfrastructure #Prefactor #LLM #DevSecOps #AgentIdentity #M2MSecurity