input_userauth_error: bad message during authentication: type 100

I am trying to connect with a server using SSH. I have been struggling with this for a few days, Earlier it used to work but after some upgrade activity at OS[AIX] level may be SSH upgrade it stopped working.

Below is the error code which it shows: input_userauth_error: bad message during authentication: type 100

I have generated ssh keys using ssh-keygen command Generating public/private rsa key pair. Enter file in which to save the key (/home/user/.ssh/id_rsa): ....

and I have shared the public key to place in the remote server.

For troubleshooting below is the code which I got with command ssh -vvv sftp user@remoteserver

OpenSSH_7.5p1, OpenSSL 1.0.2p 14 Aug 2018 debug1: Reading configuration data /etc/ssh/ssh_config debug1: Failed dlopen: /usr/krb5/lib/libkrb5.a(libkrb5.a.so): Could not load module /usr/krb5/lib/libkrb5.a(libkrb5.a.so). System error: No such file or directory

debug1: Error loading Kerberos, disabling Kerberos auth. debug2: resolving "195.35.XXX.191" port 22 debug2: ssh_connect_direct: needpriv 0 debug1: Connecting to 195.35.XXX.191 [195.35.XXX.191] port 22. debug1: Connection established. debug1: key_load_public: No such file or directory debug1: identity file /home/user/.ssh/id_rsa type -1 debug1: key_load_public: No such file or directory debug1: identity file /home/user/.ssh/id_rsa-cert type -1 debug1: key_load_public: No such file or directory debug1: identity file /home/user/.ssh/id_dsa type -1 debug1: key_load_public: No such file or directory debug1: identity file /home/user/.ssh/id_dsa-cert type -1 debug1: key_load_public: No such file or directory debug1: identity file /home/user/.ssh/id_ecdsa type -1 debug1: key_load_public: No such file or directory debug1: identity file /home/user/.ssh/id_ecdsa-cert type -1 debug1: key_load_public: No such file or directory debug1: identity file /home/user/.ssh/id_ed25519 type -1 debug1: key_load_public: No such file or directory debug1: identity file /home/user/.ssh/id_ed25519-cert type -1 debug1: Enabling compatibility mode for protocol 2.0 debug1: Local version string SSH-2.0-OpenSSH_7.5 debug1: Remote protocol version 2.0, remote software version Serv-U_15.1.6.25 debug1: no match: Serv-U_15.1.6.25 debug2: fd 3 setting O_NONBLOCK debug1: Authenticating to 195.35.XXX.191:22 as 'user' debug3: hostkeys_foreach: reading file "/home/user/.ssh/known_hosts" debug3: record_hostkey: found key type RSA in file /home/user/.ssh/known_hosts:1 debug3: load_hostkeys: loaded 1 keys from 195.35.XXX.191 debug3: order_hostkeyalgs: prefer hostkeyalgs: ssh-rsa-cert-v01@openssh.com,rsa-sha2-512,rsa-sha2-256,ssh-rsa debug3: send packet: type 20 debug1: SSH2_MSG_KEXINIT sent debug3: receive packet: type 20 debug1: SSH2_MSG_KEXINIT received debug2: local client KEXINIT proposal debug2: KEX algorithms: curve25519-sha256,curve25519-sha256@libssh.org,ecdh-sha2-nistp256,ecdh-sha2-nistp384,ecdh-sha2-nistp521,diffie-hellman-group-exchange-sha256,diffie-hellman-group16-sha512,diffie-hellman-group18-sha512,diffie-hellman-group-exchange-sha1,diffie-hellman-group14-sha256,diffie-hellman-group14-sha1,ext-info-c debug2: host key algorithms: ssh-rsa-cert-v01@openssh.com,rsa-sha2-512,rsa-sha2-256,ssh-rsa,ecdsa-sha2-nistp256-cert-v01@openssh.com,ecdsa-sha2-nistp384-cert-v01@openssh.com,ecdsa-sha2-nistp521-cert-v01@openssh.com,ssh-ed25519-cert-v01@openssh.com,ecdsa-sha2-nistp256,ecdsa-sha2-nistp384,ecdsa-sha2-nistp521,ssh-ed25519 debug2: ciphers ctos: aes128-ctr,aes192-ctr,aes256-ctr,chacha20-poly1305@openssh.com,aes128-gcm@openssh.com,aes256-gcm@openssh.com,aes128-cbc,aes192-cbc,aes256-cbc debug2: ciphers stoc: aes128-ctr,aes192-ctr,aes256-ctr,chacha20-poly1305@openssh.com,aes128-gcm@openssh.com,aes256-gcm@openssh.com,aes128-cbc,aes192-cbc,aes256-cbc debug2: MACs ctos: umac-64-etm@openssh.com,umac-128-etm@openssh.com,hmac-sha2-256-etm@openssh.com,hmac-sha2-512-etm@openssh.com,hmac-sha1-etm@openssh.com,umac-64@openssh.com,umac-128@openssh.com,hmac-sha2-256,hmac-sha2-512,hmac-sha1 debug2: MACs stoc: umac-64-etm@openssh.com,umac-128-etm@openssh.com,hmac-sha2-256-etm@openssh.com,hmac-sha2-512-etm@openssh.com,hmac-sha1-etm@openssh.com,umac-64@openssh.com,umac-128@openssh.com,hmac-sha2-256,hmac-sha2-512,hmac-sha1 debug2: compression ctos: none,zlib@openssh.com,zlib debug2: compression stoc: none,zlib@openssh.com,zlib debug2: languages ctos: debug2: languages stoc: debug2: first_kex_follows 0 debug2: reserved 0 debug2: peer server KEXINIT proposal debug2: KEX algorithms: ecdh-sha2-nistp256,ecdh-sha2-nistp384,ecdh-sha2-nistp521,diffie-hellman-group14-sha1,diffie-hellman-group1-sha1 debug2: host key algorithms: ssh-rsa debug2: ciphers ctos: aes128-cbc,rijndael128-cbc,3des-cbc,blowfish-cbc,aes192-cbc,rijndael192-cbc,aes256-cbc,rijndael256-cbc,rijndael-cbc@lysator.liu.se,cast128-cbc,rijndael-cbc@lysator.liu.se,aes128-ctr,aes192-ctr,aes256-ctr debug2: ciphers stoc: aes128-cbc,rijndael128-cbc,3des-cbc,blowfish-cbc,aes192-cbc,rijndael192-cbc,aes256-cbc,rijndael256-cbc,rijndael-cbc@lysator.liu.se,cast128-cbc,rijndael-cbc@lysator.liu.se,aes128-ctr,aes192-ctr,aes256-ctr debug2: MACs ctos: hmac-md5,hmac-sha1,hmac-sha1-96,hmac-sha2-256,hmac-sha2-256-96,hmac-sha2-512,hmac-sha2-512-96 debug2: MACs stoc: hmac-md5,hmac-sha1,hmac-sha1-96,hmac-sha2-256,hmac-sha2-256-96,hmac-sha2-512,hmac-sha2-512-96 debug2: compression ctos: zlib,none debug2: compression stoc: zlib,none debug2: languages ctos: debug2: languages stoc: debug2: first_kex_follows 0 debug2: reserved 0 debug1: kex: algorithm: ecdh-sha2-nistp256 debug1: kex: host key algorithm: ssh-rsa debug1: kex: server->client cipher: aes128-ctr MAC: hmac-sha2-256 compression: none debug1: kex: client->server cipher: aes128-ctr MAC: hmac-sha2-256 compression: none debug3: send packet: type 30 debug1: sending SSH2_MSG_KEX_ECDH_INIT debug1: expecting SSH2_MSG_KEX_ECDH_REPLY debug3: receive packet: type 31 debug1: Server host key: ssh-rsa SHA256:U7gTHqAEWWcc9s4RaafFus7Ijsdvqbd/3IS8Juih3ys debug3: hostkeys_foreach: reading file "/home/user/.ssh/known_hosts" debug3: record_hostkey: found key type RSA in file /home/user/.ssh/known_hosts:1 debug3: load_hostkeys: loaded 1 keys from 195.35.XXX.191 debug1: Host '195.35.XXX.191' is known and matches the RSA host key. debug1: Found key in /home/user/.ssh/known_hosts:1 debug3: send packet: type 21 debug2: set_newkeys: mode 1 debug1: rekey after 4294967296 blocks debug1: SSH2_MSG_NEWKEYS sent debug1: expecting SSH2_MSG_NEWKEYS debug3: receive packet: type 21 debug1: SSH2_MSG_NEWKEYS received debug2: set_newkeys: mode 0 debug1: rekey after 4294967296 blocks debug2: key: /home/user/.ssh/id_rsa (0) debug2: key: /home/user/.ssh/id_dsa (0) debug2: key: /home/user/.ssh/id_ecdsa (0) debug2: key: /home/user/.ssh/id_ed25519 (0) debug3: send packet: type 5 debug3: receive packet: type 6 debug2: service_accept: ssh-userauth debug1: SSH2_MSG_SERVICE_ACCEPT received debug3: send packet: type 50 debug3: receive packet: type 51 debug1: Authentications that can continue: publickey debug3: start over, passed a different list publickey debug3: preferred publickey,keyboard-interactive,password debug3: authmethod_lookup publickey debug3: remaining preferred: keyboard-interactive,password debug3: authmethod_is_enabled publickey debug1: Next authentication method: publickey debug1: Trying private key: /home/user/.ssh/id_rsa debug3: sign_and_send_pubkey: RSA SHA256:atNggY8MW6O2BP3wlJsqTqkmSpQ4ggObtvJ/UOjFswA debug3: send packet: type 106 debug1: Sent ALLOW_PKCS12_KEYSTORE_CLIENT_FLAG packet debug3: send packet: type 50 debug2: we sent a publickey packet, wait for reply debug3: receive packet: type 100 input_userauth_error: bad message during authentication: type 100 Connection closed

Kindly advice on this

sshnet / SSH.NET

input_userauth_error: bad message during authentication: type 100 #529