CVE-2026-62990: fallo de gravedad alta en shopperlabs shopper

Shopper is a Headless e-commerce Admin Panel. In versions from 2.0.0 prior to 2.10.1 and in the 3.0.0 prereleases beta.1 and beta.2, authenticated back-office staff with a content-upload permission can store executable media on the administrator's own origin. In the 2.x implementation, relevant upload permissions include `edit_products` or `add_brands`, and `packages/admin/config/media.php` allows `image/svg+xml` in every media collection, including image fields whose image/* validation also accepts SVG. The product files collection in `packages/admin/src/Livewire/Components/Products/Form/Files.php` has no MIME restriction and accepts `text/html` as well. Media is served inline from the `public` disk under `/storage/` with its own content type, without `Content-Disposition: attachment` or a `Content-Security-Policy`. When an administrator opens an uploaded HTML or SVG file, stored script executes in that administrator's session. In 2.x, the script can invoke `packages/admin/src/Livewire/SlideOvers/CreateTeamMember.php`, whose `store()` checks `access_setting` held by the viewing administrator but trusts client-supplied `role_id`, to create a new attacker-controlled administrator with a chosen password. This account persists after the uploaded file is deleted and gives access to customer data, orders, settings, and user/role management; the same script can exfiltrate data or grant permissions to the attacker's account. Direct account creation by the low-privileged uploader is blocked, so exploitation requires the administrator to open the file. The 3.x prerelease line already excludes SVG but still allows executable product files. This issue is fixed in versions 2.10.1 and 3.0.0-beta.3.