Bitcoin Client Software and Version Number: Bitcoin Core 0.15.1
Operating System: Ubuntu
Description of Problem: I'm running a bitcoin core full node some hours a day since years now and it never got more than 8 connections.
This morning after leaving it run all night there were 10 connections (never happened before).
But two connections were from 127.0.0.1 and looked somehow "symmetrical" meaning that one was "inbound", the other was "outbound", and the amounts of "Sent" and "Received"  bytes were crossed e.g. one was Sent: 107 Kb Received: 185 Kb the other was Sent: 185 Kb Received: 107 Kb

debug.log  contains several entries in the form:
2018-01-22 xxxxxx connected to self at 127.0.0.1:xxxxx, disconnecting

While it nearly looks legit I've never seen this before so I'm wondering has my system been compromised?