Thanks for your bugreport. Those are leftovers from early apport/kernel versions. Just delete them, this shouldn't be happening anymore (but please reopen if the timestamps of the core files are very recent (within the last 10 days)).
** Changed in: Ubuntu Status: Unconfirmed => Fix Released -- Files appearing in home folder corexxxxx https://launchpad.net/bugs/64292 -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs