Lychee Vulnerable to Stored XSS via Photo Description in RSS/Atom/JSON Feed (No Sanitization on Public Endpoint)

Lychee is a free, open-source photo-management tool. Prior to version 7.5.3, the photo `description` field is stored without HTML sanitization and rendered using `{!! $item->summary !!}` (Blade unescaped output) in the RSS, Atom, and JSON feed templates. The `/feed` endpoint is publicly accessible without authentication, allowing any RSS reader to execute attacker-controlled JavaScript. Version 7.5.3 fixes the issue.