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My guess would be that your distribution has set up some sort of local management interface there. Since it's running on 127.0.0.1, it would not be accessible remotely.
My all ports are closed and I've set iptables to block everything, except some custom rules. I didn't set any rules in iptables for these particular ports. Does it mean, that some programs have control over iptables?
So, these ports are opened, because I allowed them in iptables and there is no other way, that they can be opened? Can I share my iptables configuration with you to take a quick look at it, if previous sentence is true?
As I said, you already don't need to worry about external IPs contacting those listen sockets, because they can't. You don't even need iptables rules to stop this.
Which IPs and ports your applications listen on have nothing to do with iptables.