GHSA-8vh3-g2qg-2h2c (CVSS 9.1, CWE-306): POST /webhooks/nextcloud had no
authentication when WEBHOOK_SECRET was unset (the default). The receiver
trusted the attacker-supplied user.uid and fed it to Qdrant, letting an
unauthenticated network caller delete or re-index any user's vector
embeddings.
Webhooks now require WEBHOOK_SECRET end-to-end:
- app.py: the /webhooks/nextcloud route is only mounted when WEBHOOK_SECRET
is set; otherwise it 404s and a startup warning notes vector sync falls
back to the polling scanner.
- webhook_receiver.py: removed the warn-and-accept fallback. No secret -> 503,
missing/invalid bearer -> 401; the payload is never processed unauthenticated.
- webhook_routes.py / api/webhooks.py: webhook_auth_pair() raises
WebhookSecretNotConfigured instead of returning authMethod="none"; both
registration entry points return a clear 503 so no dead unauthenticated
webhooks are created.
Also expose webhooks availability to the Astrolabe UI via GET /api/v1/status
("webhooks_enabled": bool), set WEBHOOK_SECRET on the docker-compose
semantic-search dev services, and update env.sample + ADR-010 / ADR-018 /
webhook-management-guide docs.
Vector sync still works without a secret via the polling scanner.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>