Too-long file name: which iOS app owns it?

I have an iPhone that I back up to a Mac (via iTunes), and the backup is failing. The error shown in iTunes is useless, but the console shows this:

Jan 6 20:53:58 aron-mbp.local AppleMobileBackup[71561]: ERROR: Backup message response: 101 stat error: File name too long (63) at path "/var/mobile/Containers/Data/Application/C3147DA8-A001-4A6C-BF8D-971DC2678722/Documents/iCache/http://ift.tt/14tPFDt....nT+soTf+" (MBErrorDomain/101)

(I've snipped quite a lot of characters out of the file name, as it is, in fact, extremely long.)

So, it looks like some app has created this huge-named file, which is stuffing up the backup process because iOS can't stat it and barfs.

I figure, deleting the offending app should delete the file and fix the problem. But: which app is it? All I have to go on is the unique ID or whatever it's called, C3147DA8-A001-4A6C-BF8D-971DC2678722. Is there a way to determine which app this corresponds to? I'm happy to dig through the ipa files if necessary.

(I've tried deleting the Pinterest app, given the presence of 'pinterest.com' in the path, with no luck. I've shotgunned a few others, again with no luck.)

This is iOS 8.1.2.