The ROI calculator accepted the email field with no validation at all and
stored whatever arrived, which is where the spam submissions were putting
shell-command payloads. Nothing was executable — there is no child_process
or eval in the codebase and all writes are parameterized — but the junk was
being persisted, and the field is the obvious place to stop it.
Adds security.validateEmail(), deliberately stricter than RFC 5322: the
local part is limited to the characters real addresses use, which excludes
every shell metacharacter (; | & ` $ ( ) < > \ " ' space) and CSV-injection
lead-ins. Also rejects control characters (including the CR/LF used for
mail-header injection), caps lengths at 254/64/253, rejects non-strings,
and normalizes to trimmed lowercase before storage.
Applied to /api/calculate (optional field — empty is fine, present must be
valid) and to /api/leads, replacing its much weaker regex. The client
mirrors the check for immediate feedback; the server remains authoritative.
Also hardens the /api/leads required-field checks, which called .trim() on
unvalidated input and returned a 500 rather than a 400 when a bot posted a
non-string.
Trade-off: RFC-legal but vanishingly rare addresses (foo!bar$baz@x.com, a
leading + in the local part) are rejected. Those characters are the
injection surface.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
The calculator endpoint was open to anyone, and it has been collecting
spam submissions. Add a layered guard that runs before anything is
written to the DB or sent to the AI provider:
- Cloudflare Turnstile CAPTCHA, verified server-side (active when
TURNSTILE_* keys are configured; fails closed if unverifiable)
- Honeypot field that only bots fill in
- Signed, single-use form token enforcing a 4s minimum fill time
- Per-IP rate limiting (5 per 10 min, 25 per 24h)
Layers 2-4 need no configuration and work on their own, so submissions
are throttled immediately; adding Turnstile keys upgrades it to a full
challenge. Blocked submissions now stop the flow client-side instead of
silently showing a result.
Also sets `trust proxy` for correct client IPs behind nginx, caps the
JSON body at 32kb, and fixes a latent ReferenceError in the
"AI not configured" branch that called saveCalcSubmission() before the
variables it closes over were declared.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
