RISK-F-0002: the SSH signing gate is off, and enabling it is now the unsafe move

Routed by ops-warden, which owns the defect and is the affected PEP.

ops-warden ships a flex-auth pre-sign authorization gate and runs with
policy.enabled: false in production (warden.production.example.yaml:22,
policy.py:33). Every production warden sign proceeds with no authorization
decision; possession of the scoped VAULT_TOKEN is the whole model.

That was a known, boring availability blocker (FLEX-WP-0007) until yesterday.
RISK-F-0001 changes its shape: the production config points the gate at
flex-auth.flex-auth.svc.cluster.local:8080 — the exact ClusterIP surface that
authenticates no caller. Enabling the gate before RISK-F-0001 is fixed would
convert an absent control into a false attestation, writing a
policy_decision_id into the signature log for issuances an attacker authorized
by forging the oracle. An authorization check that can be forged is worse than
none, because only one of the two lies in the record afterwards.

severity, disclosure and escalation left unset — risk-nexus's to set.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
This commit is contained in:
tegwick 2026-08-18 13:04:34 +02:00
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---
id: RISK-F-0002
type: finding
title: "ops-warden signs SSH certificates with no authorization decision, and its unblock is now unsafe"
status: open
reported_by: ops-warden
reported_via: ops-warden
routed_by: ops-warden
date_reported: "2026-08-18"
system: ops-warden
environment: production
fix_owner: ops-warden
fix_tracking: WARDEN-WP-0007 (gate shipped, disabled) / FLEX-WP-0007 (runtime deploy)
related: [RISK-F-0001]
# risk-nexus's to set, not the reporter's (INTENT, "What it does not own").
severity: unset
disclosure: unset
escalation: unset
---
# RISK-F-0002 — the SSH signing gate is off, and turning it on is now the more dangerous move
## What is true
`ops-warden` issues short-lived SSH certificates for `adm`/`agt`/`atm` actors
against production OpenBao. It ships a pre-sign authorization gate that asks
`flex-auth` whether a given actor may sign. **That gate is disabled in
production and has been since it shipped.**
Verifiable in this estate's own files:
- `ops-warden/examples/warden.production.example.yaml:22``policy.enabled: false`
- `ops-warden/src/warden/policy.py:33``if not cfg.enabled: return None`
Every production `warden sign` therefore proceeds with no authorization
decision. What still constrains it: the actor must exist in `inventory.yaml`,
TTL is enforced per actor type (`adm` 48h, `agt` 24h, `atm` 8h), the caller must
hold a scoped `VAULT_TOKEN`, and every issuance is logged. What does not
constrain it: any per-request judgement about whether this actor should be
getting this certificate right now. Possession of the signing token is the
whole authorization model.
This is a known, deliberate state, not a discovery. It is filed because
"deliberate and known" is exactly the condition that stops being tracked once
the person who decided it stops looking — and because the reason it is still
true has just changed.
## Why this is filed now rather than in June
The gate's stated blocker has always been `FLEX-WP-0007`: `flex-auth` is not
deployed at a reachable URL, so enabling a `fail_closed: true` gate would break
all signing. That is a availability blocker, and it is boring.
`RISK-F-0001` changes the shape of it. The production config points the gate at:
```
flex_auth_url: http://flex-auth.flex-auth.svc.cluster.local:8080
```
That is precisely the ClusterIP surface `RISK-F-0001` reports as authenticating
no caller. So the sequencing is no longer "enable it once flex-auth is up". It
is:
> **Enabling the gate before `RISK-F-0001` is fixed would make things worse, not
> better.**
Today, an unauthorized signing attempt is unauthorized and unrecorded as such.
With the gate on and the oracle forgeable, an attacker who can reach the
ClusterIP can obtain a genuine `allow` and the signature log will carry a
`policy_decision_id` attesting that the issuance was authorized. The gate would
convert an absent control into a **false attestation** — and the audit trail,
which currently makes no claim, would start making one that is wrong.
An authorization check that can be forged is worse than no authorization check,
because only one of the two lies in the record afterwards.
## What ops-warden is doing about it
The mechanism recommendation for `RISK-F-0001` was answered on 2026-08-17
(`ops-warden/wiki/NetKingdomSecurityMap.md`, "Service-to-service caller
authentication"): projected, audience-scoped Kubernetes ServiceAccount tokens
verified by TokenReview, with the caller's asserted `system` bound to the
authenticated ServiceAccount. `ops-warden` implements the calling side and has
committed to a warn-only rollout on `flex-auth`'s schedule.
The ordering constraint is recorded there and restated here because it is a
risk statement, not an architecture one:
```
flex-auth warn-only -> ops-warden gate presents its SA token -> logs clean
-> flex-auth fail-closed -> ops-warden policy.enabled: true
```
`policy.enabled` must not flip anywhere while `/v1/check` answers
unauthenticated callers. Nothing else is asked of `flex-auth` by this record.
## What this repo is asked to decide
1. **Severity.** Note the two states are not equally bad and the register should
probably say which it is scoring: the gate being *off* (a missing control,
honestly represented) versus the gate being *turned on prematurely* (a
present control that lies). The second is the one worth a severity.
2. **Whether this is one finding or a dependency on `RISK-F-0001`.** It is
filed separately because the fix owner differs and because the "off" state
has its own standing regardless of how `RISK-F-0001` resolves. If this repo
would rather carry it as a consequence of `RISK-F-0001` than as a peer,
that is a reasonable call and `ops-warden` will not re-file it.
3. **Escalation.** `ops-warden` does not think this needs the operator: it is
known, owned, and its dangerous failure mode is a *sequencing* error that is
now written down in both repos. Recorded so the judgement is this repo's and
not assumed.
## The general point, offered for the register's design
`RISK-F-0001` observed that four live defects were found by repos reading their
own code against a ladder, none by monitoring. This finding is a fifth, found
the same way — by reading an answer we had just given and noticing it changed
the risk of a decision we had already made and filed away as merely blocked.
The estate's habit of recording a blocker once and not revisiting it is the
thing to watch. A blocker is a claim about the world at a date. `RISK-F-0001`
invalidated this one in a day, and nothing would have re-checked it.