Require an admin session for ActiveStorage direct uploads - #85
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POST /rails/active_storage/direct_uploads ships unauthenticated, so anyone could create blob records and obtain presigned R2 PUT URLs (free storage abuse). Nothing in the app uses direct uploads — the admin markdown editor proxies through /admin/uploads — so gate the endpoint behind the same admin check as Admin::BaseController instead of leaving it open. Named before_action keeps the decoration idempotent under to_prepare reloads.
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Summary
POST /rails/active_storage/direct_uploadsis drawn by Rails with no authentication and is currently reachable in production. Anyone can createActiveStorage::Blobrecords and obtain presigned R2 PUT URLs — i.e. free writes into our storage bucket plus unbounded junk rows inactive_storage_blobs.Nothing in the app uses direct uploads anymore: the admin markdown editor uploads through
POST /admin/uploads(#84), and all other file fields are plain multipart form uploads. Rather than deleting the route (draw_routes = falsewould also remove the blob-serving routes we rely on), this gates the endpoint behind the same admin check asAdmin::BaseController, keeping it usable from the admin if direct uploads are ever wanted for large files.Changes
config/initializers/active_storage_direct_uploads.rb: decoratesActiveStorage::DirectUploadsControllerinto_preparewith abefore_actionrequiring a signed-in admin (wardenuser withadmin?), returning 401 otherwise. Uses a named method so the callback dedupes ifto_prepareruns again on reload.Testing
direct_uploadpayload returned.