Release v0.28.0: security-audit-0026 I3 + I4 (HTML-email guard + async Turnstile)
Two informational findings from the Session-0026 audit, both framework-internal defense-in-depth. No operator action: no migration, no schema/config/overlay change, no deployment-facing surface. - I3: guard the dead text/html branch in email_envelope.build_envelope. No send path passes body_html; the unused branch would emit HTML built from possibly-unescaped user content (C1 stored-XSS class in the mail channel). Passing body_html now raises NotImplementedError; the arg is kept for documented future symmetry, enabling HTML mail becomes a deliberate escape-then-unguard change. - I4: make turnstile.verify_token async. The sync httpx.post ran inside the async /auth/otc/request handler, blocking the event loop up to the 10s timeout on a slow CloudFlare call. It now awaits httpx.AsyncClient via a narrow _siteverify_post seam (tests patch the seam, not the shared AsyncClient). The sole caller (main.py) now awaits it. Tests: full backend suite 365 passed. Added a coroutine-contract unit test for verify_token and flipped the email_envelope HTML test to assert the guard. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
This commit is contained in: