Problem upgrading from 3.2 to 3.3.1

Takashi Yano
Mon Nov 8 04:11:49 GMT 2021

On Sun, 7 Nov 2021 18:44:28 -0500
"Nick Popoff" wrote:
> In other words, the 3.3.1 ssh.exe does not accept legacy kex algorithms at
> all, no matter what.  I no longer can log in to Solaris.  For example, it
> DOES NOT accept the following:
> C:/cygwin64/home/Nick> ssh.exe -o KexAlgorithms=+diffie-hellman-group14-sha1
> Unable to negotiate with port 22: no matching host key type
> found. Their offer: ssh-rsa,ssh-dss
> Version 3.2 had no problem with legacy algorithms.  Can somebody explain as
> to what is going on here.  Is it a bug?  Or a deliberate break of
> compatibility?

I think this is not due to upgrading cygwin, but due to upgrading
OpenSSH to 8.8p1.

As release note of OpenSSH 8.8p1 says, adding following lines to
~/.ssh/config will solve the issue.

Host *
	HostkeyAlgorithms +ssh-rsa
	PubkeyAcceptedAlgorithms +ssh-rsa

Takashi Yano <>

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