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1s440 08-12-2022 06:28 AM
ssh connectivity issues
 
Hi all,

when i tried to connect via ssh, then i get the below error
Code:
Unable to negotiate port 22: no matching cipher found. Their offer: 3des-cbc
If i pass ciphers to the ssh command then I get
Code:
Received disconnect port 22:2:  Client Disconnect
Can anyone suggests?

suramya 08-12-2022 06:33 AM
The *-cbc protocols have a vulnerability in them and the recent versions of SSH reject them by default.
You can try the workaround as per https://unix.stackexchange.com/quest...-rejecting-cbc but I would suggest that you upgrade the SSH version of the server as soon as possible.

- Suramya

elgrandeperro 08-12-2022 09:11 AM
On the server side, you can set the ciphers in /etc/ssh/ssshd_config:

Ciphers aes128-ctr,aes192-ctr,aes256-ctr,aes128-cbc,3des-cbc,aes192-cbc,aes256-cbc

And you can not ask for that cipher, depending on client.

Turbocapitalist 08-12-2022 09:12 AM
Quote:
Originally Posted by 1s440 (Post 6373300)
Can anyone suggests?
Suggestion: Update the server post haste.

sundialsvcs 08-17-2022 08:56 PM
Quote:
Originally Posted by Turbocapitalist (Post 6373334)
Suggestion: Update the server post haste.
Entirely agree. The server appears to be offering to conduct the conversation using a cipher that is considerably out-of-date by present standards. But also, be sure that the client is also as up-to-date as possible. Both parties need to always be "singing from the latest songbook."


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