The only thing I could try to do is DoS or maybe DDoS, if I had a bot army, that IP address & port number. Maybe now that you’ve posted that information here, someone else will go for it 
There is some evidence that relay nodes are already being probed:
… but in my measurements over the last week or so it’s only about 300 bogus connections per day: not that different from a typical web server or random failed login attempts. The consensus also with @_ilap is that the node should be able to handle the spurious connections and that no additional manual work is required.
Anyone who want to verify that number 300 could run something like this (assuming they have SimpleView logging… I don’t know if this would work for other logging schemes), which would clump the bad connections from particular IP addresses:
grep ErrorPolicySuspendPeer node.log | awk '{print $NF}' | sed 's/"//g' | sort | more
I have mostly been running that shitlist to keep the log files clear of habitual offenders and thereby make SimpleView logging easier to read, so if you’re only using the Grafana dashboard that’s not an issue for you.
The resilience of the node itself is covered here in this blog topic, including the development of what they’ve been calling the “peer to peer governor” which will automatically manage node topologies, presumably refusing connections from known bad guys:
https://iohk.io/en/blog/posts/2020/07/09/cardanos-path-to-decentralization-by-marcin-szamotulski/
According to this schedule that connection quality management will be coming out “soon” and according to Charles’ last AMA the developers returning in September are working on the peer-to-peer governor as we speak.