A browser session on its own could start TOTP enrollment or register a
security key. Combined with a pending secret counting as a factor, that let
a stolen session give itself a second factor, register a passkey with it,
and keep access after the owner changed the password.
TOTP setup and security-key registration now pass on the cookie path only
when the session signed in or completed a second factor in the last five
minutes, or when the body carries a proof in the step-up shape (password,
a confirmed authenticator code, or a passkey or security-key assertion).
The settings cards ask for that proof when the server answers
auth.reproof.required and retry the same call with it. The Bearer path is
unchanged: its elevation already is the proof.
Every route that checks a password or a factor as a re-proof now uses one
verifier and one per-account budget of five attempts per fifteen minutes,
shared with the step-up mint, and records each refused proof as
auth.mfa.failed. Passkey enrollment and password change had neither the
limit (passkey enrollment) nor the audit row (both). A structural test
freezes the set of credential-verifying routes and requires a throttle and
an audit call in each.
The assertion compared the cookie to the new session row's id, which only
held while the id WAS the cookie. Check the stored hash instead: it
proves the cookie authenticates the surviving row and that the row id
never reaches the client.
One-shot prettier pass so the new format:check gate starts from a clean
baseline. Formatting only — no behaviour change. Generator-owned and
vendored artifacts stay untouched via .prettierignore.