Pimcore is an Open Source Data & Experience Management Platform. The Pimcore thumbnail generation can be used to flood the server with large files. By changing the file extension or scaling factor of the requested thumbnail, attackers can create files that are much larger in file size than the original. This vulnerability is fixed in 11.2.4.
The product allocates a reusable resource or group of resources on behalf of an actor without imposing any restrictions on the size or number of resources that can be allocated, in violation of the intended security policy for that actor.