Discourse is an open source platform for community discussion. Without a rate limit on the POST /uploads endpoint, it makes it easier for an attacker to carry out a DoS attack on the server since creating an upload can be a resource intensive process. Do note that the impact varies from site to site as various site settings like "max_image_size_kb", "max_attachment_size_kb" and "max_image_megapixels" will determine the amount of resources used when creating an upload. The issue is patched in the latest stable, beta and tests-passed version of Discourse. Users are advised to upgrade. Users unable to upgrade should reduce "max_image_size_kb", "max_attachment_size_kb" and "max_image_megapixels" as smaller uploads require less resources to process. Alternatively, "client_max_body_size" can be reduced in Nginx to prevent large uploads from reaching the server.