rack-contrib provides contributed rack middleware and utilities for Rack, a Ruby web server interface. Versions of rack-contrib prior to 2.5.0 are vulnerable to denial of service due to the fact that the user controlled data `profiler_runs` was not constrained to any limitation. This would lead to allocating resources on the server side with no limitation and a potential denial of service by remotely user-controlled data. Version 2.5.0 contains a patch for the issue.