My Archlinux running devices does not present themselves duing ssh handshake:
$ telnet 192.168.1.151 11735 Trying 192.168.1.151... Connected to 192.168.1.151. Escape character is '^]'. SSH-2.0-OpenSSH_7.4
# telnet 188.8.131.52 1234 Trying 184.108.40.206... Connected to 220.127.116.11. Escape character is '^]'. SSH-2.0-OpenSSH_6.7p1 Raspbian-5+deb8u3
# telnet 18.104.22.168 4321 Trying 22.214.171.124... Connected to 126.96.36.199. Escape character is '^]'. SSH-2.0-OpenSSH_7.2p2 Ubuntu-4ubuntu2.1
They introduce themselves during handshake.
Does configuring system to not present themselves during handshake, increase security?
(I guess, it does, as knowledge about software and version allow to narrow search of potential security holes)
If, yes, how to configure server to not introduce it's OS version during ssh handshake? (or maybe even introduce as some other, to confuse potential adversary?)