fix(security): add input validation to CLI to prevent command injection

[triepod-ai]

Summary

Adds input validation to the CLI to prevent potential command injection vulnerabilities.

Changes

• Add isValidEnvVarName() - validates env var names match [a-zA-Z_][a-zA-Z0-9_]*
• Add isValidEnvVarValue() - rejects values containing null bytes
• Add validateEnvVars() - filters invalid env vars with warnings
• Add validateServerUrl() - validates URL protocol, warns on private IPs
• Add validateCommand() - checks for shell metacharacters, verifies command exists
• Apply validation in runWebClient() and runCli() functions
• Add 11 integration tests for validation functions

Security Impact

• Prevents command injection via malicious env var names
• Prevents string truncation via null bytes in values
• Warns users about connecting to internal addresses

Test plan

• Build passes (npm run build)
• CLI validation tests pass (11/11)
• Manual testing of edge cases
• Existing CLI functionality works

🤖 Generated with Claude Code

[olaservo]

Thanks for thinking about security! After reviewing this with the MCP security guidelines, a few notes:

Per the MCP security policy, "STDIO transport command execution to launch servers is intentional design." Since Inspector is a CLI tool where the user directly provides the command to execute, this is working as intended rather than a command injection vulnerability (which would require attacker-controlled input reaching command execution).

If you believe there's a specific attack vector where untrusted input could reach command execution, please report it through HackerOne with reproduction steps.

Additionally, Inspector V1 is in maintenance mode while V2 is under development, so larger changes like new validation frameworks are being directed to V2.

Thanks again for your interest in keeping the project secure!

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This comment was drafted with assistance from Claude (AI).

[olaservo]

Closing per the discussion above. If there's a specific attack vector, please report via HackerOne.