hermes - 💡(How to fix) Fix execute_code can leak common secret env vars and bypass terminal approval guard

Summary

The execute_code sandbox currently forwards a broad set of host environment variables using a substring blocklist plus safe prefixes. This misses common secret naming patterns such as DATABASE_URL, SLACK_WEBHOOK, AWS_ACCESS_ID, and SENTRY_DSN. In addition, Python code running inside execute_code can call the generated terminal() helper, and that path should be guarded consistently before dispatching terminal commands.

Impact

A prompt or remote gateway message that causes the model to invoke execute_code can expose credentials from the parent environment to the child process. If the child uses terminal(), dangerous commands may be dispatched without an approval check at the execute-code RPC boundary.

Affected area

• tools/code_execution_tool.py::_scrub_child_env
• tools/code_execution_tool.py::_rpc_server_loop terminal dispatch

Suggested fix

• Convert execute-code child environment construction to an explicit safe allowlist, keeping skill/config passthrough for variables that are intentionally exposed.
• Remove broad HERMES_ passthrough from default safe prefixes.
• Expand secret-name coverage for common patterns such as DSNs, webhooks, database URLs, and access IDs.
• Run terminal approval guards before dispatching sandbox terminal() calls.
• Add regression tests for environment scrubbing and terminal guard behavior.