Applications using Werkzeug to parse multipart/form-data requests are vulnerable to resource exhaustion. A specially crafted form body can bypass the Request.maxformmemorysize setting.

The Request.maxcontentlength setting, as well as resource limits provided by deployment software and platforms, are also available to limit the resources used during a request. This vulnerability does not affect those settings. All three types of limits should be considered and set appropriately when deploying an application.