whitehat-security/workplans/WHITEHAT-WP-0001-cross-tenant-evidence.md

---
id: WHITEHAT-WP-0001
type: workplan
title: "Produce the adversarial evidence the Tenancy Posture ladders require"
domain: infotech
repo: whitehat-security
status: active
owner: net-kingdom
topic_slug: whitehat-security
created: "2026-08-17"
updated: "2026-08-22"
state_hub_workstream_id: "ecc16edc-9f9b-4fc4-8fb1-96b947a59299"
---

# WHITEHAT-WP-0001 — cross-tenant evidence

## Goal

Produce, on a schedule, the adversarial evidence artifacts that NetKingdom's
*Tenancy Posture* standard requires and no repo can honestly produce about
itself — starting with the one the framework calls its highest-severity gap.

Done means: a service claiming `E2` has been attacked as an adversary holding
its runtime credential, the attempt is recorded with a date and an attacker
model, and a failure routes to `risk-nexus` rather than to a log nobody reads.

## The forcing case

*Tenancy Posture* open question 3 has been unowned since the framework was
drafted. What it calls a tenant-boundary failure the security industry calls
**Broken Object Level Authorization** — OWASP API1, top of the API Security Top
10 since that list launched, and the most commonly exploited API vulnerability
in published assessments.

The estate has no coverage for it. `rapp-postgres` runs fifteen adversarial
probes and every one targets the *consumer* boundary — service versus service.
None targets the tenant boundary *inside* a consumer, which is where the
framework says the residual risk actually lives.

## Rules of engagement — T01, and nothing else starts first

An automated facility that probes systems without written scope is
indistinguishable from the threat it models. This is the gating task and it is
not paperwork.

- **Target authorization**, the control that matters most now the facility is
  scoped to any surface we choose rather than only our own. No target without a
  recorded authorization from its responsible party. Our estate in build mode
  has standing authorization only as a prerequisite: every live run still
  needs the dated engagement record and target-owner acknowledgement defined in
  the rules of engagement. Production needs its own authorization; anything we
  do not own needs written per-engagement authorization recorded here before a
  packet is sent. A commercial relationship, public reachability, and "they
  would obviously be fine with it" are each explicitly not authorization.
- **Scope.** Which systems, which namespaces, which credentials — and a hard
  stop at the engagement boundary. A probe that discovers an adjacent system
  reports what it saw and does not follow it.
- **Prohibited actions**, stated as hard rules rather than intentions:
  no destructive operations against data the estate did not create for the
  test; no exfiltration of real tenant data even as proof of a finding —
  a count and a schema shape are proof enough; no denial-of-service against a
  shared substrate outside a declared window, because the connection ceiling
  means a saturation probe is an outage for every co-resident.
- **Credentials.** The facility holds leased credentials like any workload,
  through the sanctioned OpenBao lane. It gets no standing privilege, and
  notably **no `BYPASSRLS` and no superuser** — an attacker would not have them
  and a probe holding them proves nothing.
- **Attribution.** Every probe connection is identifiable as a probe in
  `pg_stat_activity` and in logs, so an operator investigating an anomaly can
  tell us from a real adversary in seconds.
- **Abort.** How a run is stopped, by whom, and what state it leaves behind.

**Output:** `docs/rules-of-engagement.md`, reviewed by the operator personally.
This is exactly the class of thing `risk-nexus`'s escalation duty exists for.

## Tasks

### T01 — Rules of engagement
As above. Gates everything.

```task
id: WHITEHAT-WP-0001-T01
status: done
priority: high
state_hub_task_id: "0d28fd14-1b82-4ac1-907b-02f43e8baae8"
```

Drafted in `docs/rules-of-engagement.md` on 2026-08-18 with authorization
classes, per-run records, initial target envelope, hard prohibitions,
credential/attribution rules, rate defaults, abort/cleanup and evidence
schema. The operator accepted v0.1 on 2026-08-21 with the scope recorded in
what is now §11. v0.2 (2026-08-22) adds §10, the governed test plane, as a
stricter admission control. It does not expand authorization. The acceptance
approves the operating rules and offline fixture work; it does not
pre-authorize any live target.

### T02 — The attacker model per axis

```task
id: WHITEHAT-WP-0001-T02
status: done
priority: high
state_hub_task_id: "e0070ee6-6060-4a29-bd88-f664034db28e"
```

What the adversary is assumed to hold, so a probe is judged against a threat
rather than against taste. Drawn from *Tenancy Posture* §4.3, which already
distinguishes them:

| Axis | Adversary holds | Probe answers |
|---|---|---|
| E1/E2 | A legitimate runtime credential and the ability to make ordinary requests as tenant A | Can it reach tenant B's rows? |
| E3 | The above, plus SQL execution on the connection | Can it re-`SET` the tenant GUC and read across? |
| E4 | A leaked per-tenant credential | Can it address another tenant's substrate at all? |
| P1/P2 | A co-resident consumer behaving badly within its own allowance | What degradation do neighbours experience? |
| R | A copy of a backup taken before an erasure | Is the erased data still readable? |

**Output:** `docs/attacker-model.md`, completed 2026-08-21. It separates
credential-bearing tenant attacks, omitted-predicate accidents, SQL-capable
compromise, structural credential confinement, bounded co-resident saturation,
and both R4 erasure routes. It preserves the framework's correction that E3
stops accident, not compromise: resetting the tenant GUC after SQL execution
is recorded as E3's documented limit, not misreported as an E3 conformance
failure.

### T03 — Differential cross-tenant harness (the E2 artifact)

```task
id: WHITEHAT-WP-0001-T03
status: progress
priority: high
state_hub_task_id: "742561f1-97b6-4fcc-8e06-d18508ddecae"
```

The core technique: run the same request as two tenants and compare.

- Provision two disposable tenants against a target service.
- Exercise its surface as tenant A; attempt every object identifier observed
  from tenant B's context.
- Assert: B receives a denial or an empty result. **A well-formed 200
  containing A's data is the finding**, and the harness must be built to notice
  that rather than to notice errors — both of this estate's real regressions
  produced ordinary-looking responses, a 403 and a 404, and nothing alerted.
- Capture evidence as a count and a schema shape, never as tenant data (T01).

**Acceptance:** a dated run record against every *applicable* E2 target. The
artifact is the run record, not a green tick. `tenant-engine` is registered
`not_applicable` for E2; that record is the artifact for that target.
`audit-core` remains the live E2 target and still needs a new admitted
engagement.

Implementation progress, 2026-08-22: `src/whitehat_security/differential.py`
performs owner/attacker/absent comparisons, detects fixture disclosure and
write-side state change, and persists only sanitized observations. Live entry
is `execute_authorized`, which requires a plane lease. Concrete route
inventories live in `probe-packs/`. Target honesty lives in `targets/`:
`audit-core` is applicable; `tenant-engine` is `not_applicable` (that is the
artifact, not a deferral); `flex-auth` is pending.

The 2026-08-21 production engagement IDs were cancelled without sending a
target request and are retired. ops-mason applied the foundational plane on
2026-08-22. The operator approved `WH-ENG-20260822-AUDIT-E2-01` at
2026-08-22T09:52:55Z. Target-owner acknowledgement and the custody broker
remain pending. Offline preflight must fail closed until both exist. Whitehat
will not relabel tenant-engine to finish this task.

### T04 — Prove the probes fail

```task
id: WHITEHAT-WP-0001-T04
status: done
priority: high
state_hub_task_id: "a2afc0f5-3ece-410c-864c-829a8aac30fc"
```

A probe that has only ever passed is not evidence.

Build known-bad fixtures — a service with a deliberately missing tenant
predicate — and confirm each probe fails against them. `rapp-postgres` verified
its drift check this way, by re-pinning to a bad digest and confirming exit 1;
the same discipline applies here and is not optional.

**Acceptance:** every probe in T03 demonstrated failing before any of them is
trusted passing.

Completed 2026-08-22. Five generic read/list/create/update/delete probes and
the three audit-core shaped probes pass the enforcing in-process fixture and
all produce findings when the tenant predicate is removed. Tenant-engine has
no applicable E2 identity, so its pack is not calibrated as if it were E2.
`make fixture-evidence` refreshes `evidence/offline-calibration.json`.
Target probes are still not trusted passing against a live service until a
new admitted engagement runs.

### T05 — RLS conformance under attack (the E3 artifact)

```task
id: WHITEHAT-WP-0001-T05
status: progress
priority: medium
state_hub_task_id: "6df676e7-bed5-4291-a128-eb6e9844edf2"
```

`rapp-postgres` ADR-0003 supplies an `rls_conformance` view and a template, and
states plainly that the platform's guarantee is **detection, not prevention** —
a table created by a later migration ships without a policy until something
notices. This repo is that something.

- Query the conformance view on a cadence; any row is a finding.
- Attack what the view cannot see: a session that sets no GUC must read
  nothing; a session with another tenant's value must see nothing; an insert
  attributed to another tenant must be refused.
- Attempt the documented bypasses: a `SECURITY DEFINER` function owned by the
  table owner, and a role holding `BYPASSRLS`.

**Cadence is the deliverable here, not a detail.** For a detection-based
control the interval between runs *is* the exposure window, and ADR-0003 leaves
the number to this repo. Set it, and state the resulting window in the record.

Implementation progress, 2026-08-22: the cadence is fixed at 24 hours plus run
and reporting latency, with event-triggered pre-promotion runs after schema,
role, RLS or security-definer changes. `src/whitehat_security/e3.py` encodes the
seven expected outcomes, keeps the SQL-compromise GUC reset labeled as E3's
documented limit, and calibrates known-good/known-bad in-process. `platform-pg`
is registered `pending`. A live database run still requires its separate
authorized target, named database, ordinary runtime role, and window.

### T06 — Noisy-neighbour characterisation (the P1/P2 artifact)

```task
id: WHITEHAT-WP-0001-T06
status: progress
priority: medium
state_hub_task_id: "99254ab5-f08e-44c7-8399-be706dc03019"
```

The framework had to reword this artifact once already: its first draft
required proof that a saturating consumer "does not breach" another's
allowance, which shared infrastructure cannot provide.

What is achievable and therefore what this produces: a recorded baseline of
per-consumer resource usage; a run in which one consumer saturates its declared
allowance; evidence that the governance controls **bind**; and the degradation
co-residents experience, **measured and written down** rather than asserted
acceptable.

Runs inside a declared window per T01 — on a single-node rail with a six-
consumer connection ceiling, a saturation probe is an outage if run carelessly.

Implementation progress, 2026-08-22: `src/whitehat_security/capacity.py`
records baseline/loaded latency, errors and throughput per consumer, governor
binding, aggressor peak/ceiling and neighbour degradation. The in-process
fixture is registered as `fixture-capacity`. `shared-substrate` is `pending`.
No live load has been generated; the required operator-approved substrate
window and aggressor ceiling do not yet exist.

### T07 — Reporting into risk-nexus

```task
id: WHITEHAT-WP-0001-T07
status: progress
priority: medium
state_hub_task_id: "54f33288-5361-4b20-8e1f-168866d64644"
```

Findings leave this repo in one direction. A run produces: what was attempted,
under which attacker model, when, against which posture claim, and the outcome.
It carries no severity — that is `risk-nexus`'s.

A **passing** run is also reported. "The attacks we thought of did not work" is
the honest claim, and recording it dated is what lets anyone see how stale the
assurance has become.

Implementation progress, 2026-08-22: `schemas/run-report.schema.json` defines
the minimized evidence contract, `whitehat risk-message` renders both pass
and finding deliveries without severity, and `whitehat deliver` queues a
target report to `outbox/`. Fixture calibration is refused as target
assurance. Completion awaits the first authorized target report being
delivered to `risk-nexus`.

### T08 — Governed test plane

The 2026-08-22 cutoff's missing infrastructure, encoded here so live work can
resume later without assembling authority during the run.

```task
id: WHITEHAT-WP-0001-T08
status: done
priority: high
state_hub_task_id: "965ab027-efde-48b7-bb13-84dd308b909d"
```

Completed 2026-08-22 as a repository contract, not a cluster provision:

- Target registration schema and catalog, including an honest
  `not_applicable` state.
- Fail-closed admission: retired IDs, kill switch, approval class, namespace,
  pinned digest, known-bad calibration, two identity handles.
- Credential broker interface that never returns secret values. The live
  broker is unconnected and raises before any custody call.
- Rate watcher, lease cleanup, default-deny plane manifests, runner identity.
- Automatic outbox delivery of target reports only.

`ops-mason` was asked on 2026-08-22 to provision only the namespace, default
deny policy and runner service account from `plane/`. That message does not
authorize a pod, a credential, or traffic. A real custody projection still
waits on a new engagement ID.

## Sequencing

T01 gates all. T02 shapes T03/T05/T06. T04 gates trusting any of them. T08
gates live T03. T07 can follow T03.

## Session cutoff — 2026-08-22

The coordinating session ended with the workplan deliberately **active**. T01,
T02, T04 and T08 are done. T03, T05, T06 and T07 remain in progress. The two
dated production engagement records were cancelled without sending any target
request; cancelled engagement IDs are terminal and must never be reused.

The offline instrument is implemented, calibrated, and plane-gated. The
estate still has to provision the cluster plane and a value-safe credential
broker before any live evidence exists. Resume only with new engagement IDs.
The exact completed scope is recorded in `docs/session-cutoff-2026-08-22.md`
and `docs/test-plane.md`.

## Risks

**The facility becomes the threat.** Mitigated by T01, and by holding no
standing privilege.

**Probes weaken silently.** A probe that starts passing after a change to
itself rather than to the system is a finding, not a fix. Probe changes are
reviewed as security changes.

**Green is mistaken for safe.** Every report states that a pass means the
attacks attempted did not work, not that the boundary holds.

**It drifts into fixing things.** The boundary in INTENT is load-bearing:
findings route out, work does not come in.

## Open questions

1. **Owner: NetKingdom** — settled 2026-08-17. Offensive security is security
   work. The residual tension (NetKingdom owning both the Tenancy Posture
   framework and the facility that tests conformance to it) is mitigated by
   findings routing out to `risk-nexus` under separate ownership, and is
   recorded in INTENT rather than argued away.
2. **Where probes run from.** In-cluster gives realistic network position;
   outside gives independence from the substrate under test. Probably both,
   eventually; pick one to start.
3. **Does a service get told it is being probed?** Announced runs are easier to
   operate; unannounced ones test the alerting too. Build mode probably
   announced, production probably not — which is itself a T01 decision.