Created attachment 11657 [details]
Potential fix. MIT license.
When hosting an HTTP server (for example, a Nancy self-hosted process) an empty line in the request can cause the worker thread to spin forever, pegging the CPU. This occurs on line 347 of mcs/class/System/System.Net/HttpConnection.cs. The problem seems to be present in master.
The issue is consistently reproducible by telnetting to a hosting process and simply hitting enter.
I've attached the patch I'm using to work around the problem, provided under the MIT license.
Apologies - the line number referenced above should be 323, not 347.