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Security audit

mcporter

Security checks for vulnerabilities and agentic risk

Overview

This skill is a thin, disclosed guide for using the mcporter CLI with MCP servers, but users should treat remote endpoints and auth commands carefully.

Install only if you intend to let agents use mcporter to contact MCP servers. Use trusted endpoints, avoid placing secrets in tool arguments unless necessary, review auth/config changes, and stop the daemon when you do not need persistent MCP access.

Vulnerability Patterns
  • Skill Instruction HijackingAlters the agent's session goals or safety constraints when the skill loads
  • Agent Memory PoisoningWrites attacker-controlled rules into memory that affect later sessions
  • Remote Payload Retrieval and ExecutionFetches external code whose behavior can change after review
  • Embedded Malicious CodeShips malicious scripts inside the skill and executes them locally
  • Unauthorized Access and Privilege EscalationObtains permissions beyond the task's legitimate needs
Vulnerability Patterns
  • Data ExfiltrationExternal Transmission, Env Variable Harvesting, File System Enumeration
  • Prompt InjectionInstruction Override, Hidden Instructions, Exfiltration Commands
  • Privilege EscalationExcessive Permissions, Sudo/Root Execution, Credential Access
  • Supply ChainUnpinned Dependencies, External Script Fetching, Obfuscated Code
  • Excessive AgencyUnrestricted Tool Access, Autonomous Decision Making, Scope Creep
Findings (2)

External Transmission

Medium
Category
Data Exfiltration
Content
- Selector: `mcporter call linear.list_issues team=ENG limit:5`
- Function syntax: `mcporter call "linear.create_issue(title: \"Bug\")"`
- Full URL: `mcporter call https://api.example.com/mcp.fetch url:https://example.com`
- Stdio: `mcporter call --stdio "bun run ./server.ts" scrape url=https://example.com`
- JSON payload: `mcporter call <server.tool> --args '{"limit":5}'`
Confidence
87% confidence
Finding
The example `mcporter call https://api.example.com/mcp.fetch url:https://example.com` demonstrates direct outbound network access to an arbitrary remote MCP endpoint. In context, this is expected functionality rather than overtly malicious behavior, but without accompanying warnings or guardrails it can facilitate sending sensitive data to external infrastructure.

Missing User Warnings

Medium
Confidence
92% confidence
Finding
The skill explicitly documents tool invocations that can contact remote MCP endpoints or fetch external URLs, but it does not disclose that prompts, arguments, tokens, or other sensitive data may be transmitted to third-party services. In a skill designed to bridge to arbitrary HTTP or stdio-backed MCP servers, that omission increases the risk of unintended data exfiltration or user misuse.

Static analysis

No suspicious patterns detected.