You can easily reproduce it by building and launching the open source iOS ownCloud client at https://github.com/owncloud/ios-app:
git clone https://github.com/owncloud/ios-app
cd ios-app
git submodule init
git submodule update
open ownCloud.xcodeproj
Build & Run and it crashes right in -[NSURLSession sessionWithConfiguration:delegate:delegateQueue:] (within -[__CFN_ConnectionContextManager registerSession:]).
Topic:
App & System Services
SubTopic:
Networking
Tags: