OpenSSH on Windows, ssh cannot |bind()| localport to port < 1023

Roland Mainz roland.mainz at
Sun Nov 12 00:22:29 AEDT 2023



I'm doing some testing with the ssh client OpenSSH on Windows 10
(10.0-19045) but due to firewall restrictions I need to run my
experiments from a local port < 1024 (not negotiable).

I thought that this was no problem... but ssh |bind()| fails with
"address in use" (yes, I checked netstat, no one is there) for any
port < 1023.
Then I checked $ netstat # and $ netsh int ipv4 show excludedportrange
protocol=tcp # and the same for IPv6, noone is using ports.

This *feels* like the "restricted port range" (1-1023) on UNIX/Linux,
where only "root" can do a |bind()| with a local port < 1023, but this
is Windows, and even as "Administrator" this still fails.
talks about a "... well-known ports that are used by services and
applications...", but I do not know where to set that (for a Cygwin

Does anyone know what is going on ? Is there a way around this ?


  __ .  . __
 (o.\ \/ /.o) roland.mainz at
  \__\/\/__/  MPEG specialist, C&&JAVA&&Sun&&Unix programmer
  /O /==\ O\  TEL +49 641 3992797
 (;O/ \/ \O;)

More information about the openssh-unix-dev mailing list