Close two malicious-input gaps flagged in the suite review: XSS was only fuzzed
through display_name, and the SSE ticket flow had no security assertions.
xss-injection:
- Stored XSS in captions — upload with each XSS payload as the caption, mark it
feed-visible, render /feed and assert window.__xssFired stays false, no dialog
fires, and no live `img[onerror]`/`<script>` element is produced (Svelte escaping
renders it as inert text). A trailing CAPMARK gates the assertion on the caption
actually having rendered, so it can't pass vacuously.
- Stored XSS in comments — post the two render-executing payloads as a comment,
open the lightbox (which loads comments) and assert the same inert-render props.
sse-ticket-abuse (new):
- Minting a ticket requires auth (POST /stream/ticket without Bearer → 401).
- Single-use: after the first open consumes the ticket, replaying it → 401 (a 200
would be capability replay). The first open (→200) also proves a fresh ticket works.
- An unminted/garbage ticket → 401.
All verified green against the live backend.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
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