I just upgraded two machines from Debian 9 to Debian 10 and now, when I'm connecting to them using SSH, I'm getting the following warning:
agent key RSA SHA256:[hash] returned incorrect signature type
I have been using the exact same setup before and nobody was complaining.
Even though it doesn't have any impact on the ability to successfully connect, I would like to understand what it exactly means and how to fix it.
This is the
ssh -vvv output:
debug3: sign_and_send_pubkey: RSA SHA256:[hash] debug3: sign_and_send_pubkey: signing using rsa-sha2-512 agent key RSA SHA256:[hash] returned incorrect signature type debug3: sign_and_send_pubkey: signing using ssh-rsa
Do I understand it right that my SSH client is using a hashing algorithm to sign the key the SSH server doesn't like? Or is it SSH agent? How to configure it properly so the SSH server is not complaining, please?
I don't understand what's expected and what's actually used, confused by the
SHA256: prefix vs. the message
signing using rsa-sha2-512.