The first key-exchange algorithm supported by the server is diffie-hellman-group1-sha1, which is no longer secure. Aborting connection. code example

Example: no matching key exchange method found. Their offer: diffie-hellman-group1-sha1,diffie-hellman-group14-sha1

ssh -oKexAlgorithms=+diffie-hellman-group1-sha1 123.123.123.123