An adversarial pass found 5 Critical XSS sinks where props declared number/enum
in TypeScript were interpolated raw into exported HTML attribute values,
trusting the type — but nothing enforces it at runtime (AI update_props only
validates node_id; deserialized saved state is untyped JSON). Fixed all 5
(NumberCounter data-target, StarRating aria-label, FormContainer method,
ContactForm/InputField input type) plus 6 sibling sinks found by an exhaustive
audit of every attribute-value interpolation across src/components: a
JS-source injection into ContentSlider's inline setInterval script, a
prototype-pollution-adjacent allowlist gap in Section's divider-shape lookup,
TextareaField rows, Testimonials rating aria-label, HeroSimple textAlign, and
MapEmbed zoom. Adds shared sanitizeFormMethod/sanitizeInputType allowlist
helpers to utils/escape.ts alongside the existing escapeAttr/safeUrl/cssValue
primitives. Every fix is TDD'd: a malicious-value test reproduces the raw
injection against the pre-fix code, then passes after the fix.
502 tests green (npx vitest run), tsc + vite build green (npm run build).
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Entity-escaping alone doesn't protect JS-string or raw-HTML sinks:
- HtmlBlock.toHtml exported props.code raw; now runs it through the
same purifyHtml (DOMPurify) config already used for the live editor
preview, so <script>/on*= payloads can't survive export either.
- Countdown.toHtml interpolated targetDate directly into
`new Date("${targetDate}")` inside an inline <script> -- a value
like `2026-01-01");alert(1)//` broke out of the string literal. Now
validated against a strict date/datetime shape and JSON.stringify'd
before embedding, falling back to `new Date()` for anything invalid.
- Gallery.toHtml's lightbox used
`onclick="${id}_open('${esc(img.src)}')"`, which a single quote in
img.src could break out of. Replaced with a `data-lb-src` attribute
per thumbnail and one delegated click listener on the grid
(`e.target.closest('[data-lb-src]')`) instead of a per-item inline
handler string.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
shadowdaoandClaude Opus 4.8