Two HIGH-severity findings from the security review:
- ForwardAuth: when no host header was present, /api/verify skipped the
application lookup and group check entirely, returning 200 with identity
headers (including all of the user's groups). This bypassed per-domain
access control. Now fails closed with 403, and the unreachable
DEFAULT_HEADERS fallback (the bypass path) is removed so headers are
always scoped to a resolved, active application.
- OIDC: the consent endpoint was in the verify_authenticity_token skip
list, so a forged cross-site POST could silently grant OAuth scopes.
Removed :consent from the skip list (the form already embeds the token).
Adds regression tests for both: fail-closed with no identity headers when
host is absent, and 422 on a tokenless consent POST.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>