Subprocesses spawned by the terminal tool, execute_code, Docker backend, and
the codex app-server could inherit Hermes-internal secrets that the name-based
`_HERMES_PROVIDER_ENV_BLOCKLIST` can't enumerate, because they're injected into
`os.environ` at runtime under dynamic names:
- `AUXILIARY_<TASK>_API_KEY` / `AUXILIARY_<TASK>_BASE_URL` — per-task side-LLM
credentials bridged from `config.yaml[auxiliary]` by gateway/run.py and cli.py
(vision, web_extract, approval, compression, plugin-registered tasks). Often
separate, higher-spend keys plus base URLs pointing at private endpoints.
- `GATEWAY_RELAY_*_SECRET` / `_KEY` / `_TOKEN` — relay-auth material provisioned
by gateway/relay.
Additionally, agent/transports/codex_app_server.py built its spawn env from a
raw `os.environ.copy()`, bypassing the centralized `hermes_subprocess_env()`
helper entirely — handing every codex subprocess the full Tier-1 secret set
(GH_TOKEN, gateway bot tokens, Modal/Daytona infra tokens, dashboard session
token) unfiltered. This is the #29157 sibling spawn-site gap; copilot_acp_client
already routes through the helper.
Fix — single chokepoint:
- Add `_is_hermes_internal_secret(key)` in tools/environments/local.py as the
single source of truth for the dynamic secret patterns. Matches
AUXILIARY_*_API_KEY / _BASE_URL and GATEWAY_RELAY_*_SECRET/_KEY/_TOKEN; leaves
non-secret AUXILIARY_*_PROVIDER/_MODEL and GATEWAY_RELAY routing hints visible.
- Wire the predicate into every spawn path unconditionally (ignores skill
env_passthrough opt-in AND inherit_credentials — a model-driving CLI never
needs these): `_sanitize_subprocess_env` (both loops), `_make_run_env`
(foreground), `hermes_subprocess_env` (Tier-1), and the Docker forward filter.
- Add the static GATEWAY_RELAY_* names to `_HERMES_PROVIDER_ENV_BLOCKLIST` so the
exact-match path catches them independently of the predicate.
- Add the GATEWAY_RELAY_ID/_SECRET/_DELIVERY_KEY triplet to `_ALWAYS_STRIP_KEYS`
(Tier-1) so it is stripped unconditionally on EVERY spawn surface — including
the codex/copilot `inherit_credentials=True` path that skips the Tier-2
blocklist. `_SECRET`/`_DELIVERY_KEY` are already predicate-matched; `_ID` has
no secret suffix, so enumerating it here is what closes its leak on the
inherit path (self-review W1).
- Defense in depth: env_passthrough.py `_is_hermes_provider_credential()` now
consults the same predicate, so a skill can't register these names as
passthrough and tunnel them into an execute_code / terminal child.
- Route codex_app_server through `hermes_subprocess_env(inherit_credentials=True)`
— strips Tier-1 + dynamic-internal secrets while provider creds (which codex
needs to authenticate) still flow.
Consolidates PRs #53715 (necoweb3 — the _is_hermes_internal_secret backbone +
Docker filter), #53503 (srojk34 — env_passthrough guard), and #55709 (srojk34 —
codex routing). Retires #52348 (claudlos): its copilot half is already on main,
and its codex half used the full-strip `_sanitize_subprocess_env` which would
break codex provider auth — the correct tier is `inherit_credentials=True`.
Tests: TestHermesInternalDynamicSecrets (terminal + predicate + passthrough
override), TestInternalDynamicSecrets (hermes_subprocess_env both tiers),
TestSpawnEnvSecretStripping (codex spawn env), plus env_passthrough
defense-in-depth cases.
Co-authored-by: necoweb3 <sswdarius@gmail.com>
Co-authored-by: srojk34 <286497132+srojk34@users.noreply.github.com>
Co-authored-by: claudlos <claudlos@agentmail.to>
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