[SOLVED] WS-FTP unable to connect to server after software update

mfoley · 02-19-2016, 02:23 PM

I have a bit of an authentication problem. I updated some packages on my Slackware64 14.1 system yesterday. Today, when a client was trying to WS-FTP to his account, he was blocked. The WS-FTP log is below. I've tried restarting openSSH. I can ssh to this account, but the client cannot WS-FTP. I'm sure it has something to do with the update, but I don't have any idea where to look. Need help

Code:

KexInitPacket (Client):  no kex guess present
KexAlgorithms
diffie-hellman-group-exchange-sha1,diffie-hellman-group1-sha1
00:  diffie-hellman-group-exchange-sha1
01:  diffie-hellman-group1-sha1
.
.
.
Failure to agree with SSH server on compatible algorithms
SSH Transport agreed algorithms
     Purpose: key agreement             Algo: invalid
     Purpose: server host key           Algo: ssh-rsa
     Purpose: encryption cs             Algo: aes128-ctr
     Purpose: encryption sc             Algo: aes128-ctr
     Purpose: MAC cs                    Algo: hmac-sha1
     Purpose: MAC sc                    Algo: hmac-sha1
     Purpose: compression cs            Algo: none
     Purpose: compression sc            Algo: none
Failed SSH Key Exchange
SSH Transport closed.

Emerson · 02-20-2016, 07:01 AM

There have been some changes in openSSH default configuration. I do not use WS-FTP so I can't tell how to reconfigure it, you may need to recompile with different options.

mfoley · 03-01-2016, 11:00 PM

The answer is that our latest update to OpenSSL disabled by default some encryption Algorithms because they are considered too "weak". See: http://www.openssh.com/legacy.html. diffie-hellman-group1-sha1 is specifically mentioned.

Our WS-FTP partner is going to upgrade on their end.