# Zastava Runtime Signals Gaps (ZR1–ZR10)

**Source:** `docs/product-advisories/31-Nov-2025 FINDINGS.md`
**Compiled:** 2025-12-02 (UTC)
**Scope:** Close ZR1–ZR10 for Observer + Webhook (Surface.Env/Secrets/FS) with offline parity and auditability.

## Gap remediation summary
- **ZR1 · Canonical schemas & hashing**
  - Publish signed JSON Schemas for Observer emission and Webhook admission envelopes under `docs/modules/zastava/schemas/`.
  - Enforce JCS canonical JSON; compute `sha256` over canonical form; include test vectors.
  - Validators reject non-canonical payloads; DSSE required on bundles.
- **ZR2 · Tenant isolation & scope binding**
  - Require `tenant_id` and `project_id` on all Observer/Webhook requests; fail closed on missing/ambiguous values.
  - Add tenancy annotations to DSSE envelopes and enforce tenancy in admission allowlist.
  - Add cross-tenant negative tests.
- **ZR3 · Determinism & time source**
  - Use monotonic clock + UTC; standardize ordering: `tenant -> namespace -> workload -> digest`.
  - Add multi-run hash CI to ensure stable serialization.
- **ZR4 · Provenance & signer identity**
  - Require DSSE envelopes with fields: `sensor_id`, `firmware_version`, `policy_hash`, `graph_revision_id`, `signer_key_id`.
  - Reject unsigned/unknown signer; log provenance to CAS.
- **ZR5 · Admission side-effects & escape hatches**
  - Side-effect allowlist documented; deny non-listed hooks.
  - Bypass/debug require dual approval and DSSE waiver with expiry; log and alert on use.
- **ZR6 · Offline/air-gap parity**
  - Provide `zastava-kit` bundle (admissions + observations + schemas + DSSE + hashes) with deterministic tar flags (`--mtime @0 --owner 0 --group 0 --numeric-owner | zstd -19 --long=27`).
  - Include `verify.sh` for hash/signature/tenant checks; no network dependencies.
- **ZR7 · Replay/audit linkage**
  - Embed `ledger_id` and `replay_manifest` refs in events/admissions; store in CAS.
  - Export linkage in offline kit and Evidence Locker.
- **ZR8 · Thresholds, burn-rate & anomaly policy**
  - Versioned `thresholds.yaml` with DSSE signatures; change log required.
  - Alerts on threshold change; publish budgets (latency, error rate, drop rate).
- **ZR9 · PII/redaction & log hygiene**
  - Redaction allowlist + size limits; CI + ingest PII/secret scan.
  - Truncate with omission counts; include `redaction_manifest` in DSSE annotations.
- **ZR10 · Health, kill-switch & fallback**
  - Fault counter + kill-switch with DSSE-signed disable record.
  - Configurable fail-open/closed (default fail-closed for admission); manual re-enable requires DSSE record.

## Artefacts created
- This remediation plan: `docs/modules/zastava/gaps/2025-12-02-zr-gaps.md` (to be cross-linked from sprint 0144 and TASKS).
- Delivery paths for schemas/thresholds/kit will be added when produced; DSSE signatures required for all artefacts.

## Next steps
1) ✅ Schemas + test vectors generated and DSSE-signed under `docs/modules/zastava/schemas/` (2025-12-02).
2) ✅ `thresholds.yaml` DSSE-signed and included in kit (2025-12-02).
3) ✅ Deterministic `zastava-kit` bundle + `verify.sh` built; kit DSSE stored at `docs/modules/zastava/kit/zastava-kit.tzst.dsse` with hashes in `SHA256SUMS` (2025-12-02).
4) Add tenancy/ordering/provenance enforcement to Observer/Webhook validators and tests; mirror changes in sprint and TASKS boards.
5) Upload DSSE artefacts + kit to Evidence Locker paths in `docs/modules/zastava/evidence/README.md` and backfill operations docs with verifier usage.