@kamaln7 sure, the full output is:
$ssh -vvv git@github.com
OpenSSH_6.2p2, OSSLShim 0.9.8r 8 Dec 2011
debug1: Reading configuration data /Users/acandael/.ssh/config
debug1: Reading configuration data /etc/ssh_config
debug1: /etc/ssh_config line 20: Applying options for *
debug2: ssh_connect: needpriv 0
debug1: Connecting to github.com [192.30.252.128] port 22.
debug1: Connection established.
debug3: Incorrect RSA1 identifier
debug3: Could not load "/Users/myusername/.ssh/id_rsa" as a RSA1 public key
debug1: identity file /Users/myusername/.ssh/id_rsa type 1
debug1: identity file /Users/myusername/.ssh/id_rsa-cert type -1
debug1: identity file /Users/myusername/.ssh/id_dsa type -1
debug1: identity file /Users/myusername/.ssh/id_dsa-cert type -1
debug1: Enabling compatibility mode for protocol 2.0
debug1: Local version string SSH-2.0-OpenSSH_6.2
debug1: Remote protocol version 2.0, remote software version libssh-0.6.0
debug1: no match: libssh-0.6.0
debug2: fd 3 setting O_NONBLOCK
debug3: load_hostkeys: loading entries for host "github.com" from file "/Users/acandael/.ssh/known_hosts"
debug3: load_hostkeys: found key type RSA in file /Users/acandael/.ssh/known_hosts:4
debug3: load_hostkeys: loaded 1 keys
debug3: order_hostkeyalgs: prefer hostkeyalgs: ssh-rsa-cert-v01@openssh.com,ssh-rsa-cert-v00@openssh.com,ssh-rsa
debug1: SSH2_MSG_KEXINIT sent
debug1: SSH2_MSG_KEXINIT received
debug2: kex_parse_kexinit: diffie-hellman-group-exchange-sha256,diffie-hellman-group-exchange-sha1,diffie-hellman-group14-sha1,diffie-hellman-group1-sha1
debug2: kex_parse_kexinit: ssh-rsa-cert-v01@openssh.com,ssh-rsa-cert-v00@openssh.com,ssh-rsa,ssh-dss-cert-v01@openssh.com,ssh-dss-cert-v00@openssh.com,ssh-dss
debug2: kex_parse_kexinit: aes128-ctr,aes192-ctr,aes256-ctr,arcfour256,arcfour128,aes128-gcm@openssh.com,aes256-gcm@openssh.com,aes128-cbc,3des-cbc,blowfish-cbc,cast128-cbc,aes192-cbc,aes256-cbc,arcfour,rijndael-cbc@lysator.liu.se
debug2: kex_parse_kexinit: aes128-ctr,aes192-ctr,aes256-ctr,arcfour256,arcfour128,aes128-gcm@openssh.com,aes256-gcm@openssh.com,aes128-cbc,3des-cbc,blowfish-cbc,cast128-cbc,aes192-cbc,aes256-cbc,arcfour,rijndael-cbc@lysator.liu.se
debug2: kex_parse_kexinit: hmac-md5-etm@openssh.com,hmac-sha1-etm@openssh.com,umac-64-etm@openssh.com,umac-128-etm@openssh.com,hmac-sha2-256-etm@openssh.com,hmac-sha2-512-etm@openssh.com,hmac-ripemd160-etm@openssh.com,hmac-sha1-96-etm@openssh.com,hmac-md5-96-etm@openssh.com,hmac-md5,hmac-sha1,umac-64@openssh.com,umac-128@openssh.com,hmac-sha2-256,hmac-sha2-512,hmac-ripemd160,hmac-ripemd160@openssh.com,hmac-sha1-96,hmac-md5-96
debug2: kex_parse_kexinit: hmac-md5-etm@openssh.com,hmac-sha1-etm@openssh.com,umac-64-etm@openssh.com,umac-128-etm@openssh.com,hmac-sha2-256-etm@openssh.com,hmac-sha2-512-etm@openssh.com,hmac-ripemd160-etm@openssh.com,hmac-sha1-96-etm@openssh.com,hmac-md5-96-etm@openssh.com,hmac-md5,hmac-sha1,umac-64@openssh.com,umac-128@openssh.com,hmac-sha2-256,hmac-sha2-512,hmac-ripemd160,hmac-ripemd160@openssh.com,hmac-sha1-96,hmac-md5-96
debug2: kex_parse_kexinit: none,zlib@openssh.com,zlib
debug2: kex_parse_kexinit: none,zlib@openssh.com,zlib
debug2: kex_parse_kexinit:
debug2: kex_parse_kexinit:
debug2: kex_parse_kexinit: first_kex_follows 0
debug2: kex_parse_kexinit: reserved 0
debug2: kex_parse_kexinit: ecdh-sha2-nistp256,diffie-hellman-group14-sha1,diffie-hellman-group1-sha1
debug2: kex_parse_kexinit: ssh-dss,ssh-rsa
debug2: kex_parse_kexinit: aes256-ctr,aes192-ctr,aes128-ctr,aes256-cbc,aes192-cbc,aes128-cbc,blowfish-cbc,3des-cbc,des-cbc-ssh1
debug2: kex_parse_kexinit: aes256-ctr,aes192-ctr,aes128-ctr,aes256-cbc,aes192-cbc,aes128-cbc,blowfish-cbc,3des-cbc,des-cbc-ssh1
debug2: kex_parse_kexinit: hmac-sha1,hmac-sha2-256,hmac-sha2-512
debug2: kex_parse_kexinit: hmac-sha1,hmac-sha2-256,hmac-sha2-512
debug2: kex_parse_kexinit: none,zlib,zlib@openssh.com
debug2: kex_parse_kexinit: none,zlib,zlib@openssh.com
debug2: kex_parse_kexinit:
debug2: kex_parse_kexinit:
debug2: kex_parse_kexinit: first_kex_follows 0
debug2: kex_parse_kexinit: reserved 0
debug2: mac_setup: found hmac-sha1
debug1: kex: server->client aes128-ctr hmac-sha1 none
debug2: mac_setup: found hmac-sha1
debug1: kex: client->server aes128-ctr hmac-sha1 none
debug2: dh_gen_key: priv key bits set: 163/320
debug2: bits set: 1032/2048
debug1: sending SSH2_MSG_KEXDH_INIT
debug1: expecting SSH2_MSG_KEXDH_REPLY
debug1: Server host key: RSA 16:27:ac:a5:76:28:2d:36:63:1b:56:4d:eb:df:a6:48
debug3: load_hostkeys: loading entries for host "github.com" from file "/Users/acandael/.ssh/known_hosts"
debug3: load_hostkeys: found key type RSA in file /Users/myusername/.ssh/known_hosts:4
debug3: load_hostkeys: loaded 1 keys
debug3: load_hostkeys: loading entries for host "192.30.252.128" from file "/Users/acandael/.ssh/known_hosts"
debug3: load_hostkeys: found key type RSA in file /Users/myusername/.ssh/known_hosts:5
debug3: load_hostkeys: loaded 1 keys
debug1: Host 'github.com' is known and matches the RSA host key.
debug1: Found key in /Users/myusername/.ssh/known_hosts:4
debug2: bits set: 998/2048
debug1: ssh_rsa_verify: signature correct
debug2: kex_derive_keys
debug2: set_newkeys: mode 1
debug1: SSH2_MSG_NEWKEYS sent
debug1: expecting SSH2_MSG_NEWKEYS
debug2: set_newkeys: mode 0
debug1: SSH2_MSG_NEWKEYS received
debug1: Roaming not allowed by server
debug1: SSH2_MSG_SERVICE_REQUEST sent
debug2: service_accept: ssh-userauth
debug1: SSH2_MSG_SERVICE_ACCEPT received
debug2: key: /Users/acandael/.ssh/id_rsa (0x7fe960d007d0),
debug2: key: /Users/acandael/.ssh/id_dsa (0x0),
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: Offering RSA public key: /Users/acandael/.ssh/id_rsa
debug3: send_pubkey_test
debug2: we sent a publickey packet, wait for reply
debug1: Server accepts key: pkalg ssh-rsa blen 279
debug2: input_userauth_pk_ok: fp 82:db:41:74:36:dc:c5:d9:ae:3b:9c:32:b6:c4:d2:60
debug3: sign_and_send_pubkey: RSA 82:db:41:74:36:dc:c5:d9:ae:3b:9c:32:b6:c4:d2:60
debug1: read PEM private key done: type RSA
debug1: Authentication succeeded (publickey).
Authenticated to github.com ([192.30.252.128]:22).
debug1: channel 0: new [client-session]
debug3: ssh_session2_open: channel_new: 0
debug2: channel 0: send open
debug1: Entering interactive session.
debug2: callback start
debug2: fd 3 setting TCP_NODELAY
debug3: packet_set_tos: set IP_TOS 0x10
debug2: client_session2_setup: id 0
debug2: channel 0: request pty-req confirm 1
debug1: Sending environment.
debug3: Ignored env TERM_PROGRAM
debug3: Ignored env SHELL
debug3: Ignored env TERM
debug3: Ignored env TMPDIR
debug3: Ignored env Apple_PubSub_Socket_Render
debug3: Ignored env TERM_PROGRAM_VERSION
debug3: Ignored env TERM_SESSION_ID
debug3: Ignored env USER
debug3: Ignored env SSH_AUTH_SOCK
debug3: Ignored env __CF_USER_TEXT_ENCODING
debug3: Ignored env PATH
debug3: Ignored env __CHECKFIX1436934
debug3: Ignored env PWD
debug3: Ignored env EDITOR
debug3: Ignored env SHLVL
debug3: Ignored env HOME
debug3: Ignored env LOGNAME
debug1: Sending env LC_CTYPE = UTF-8
debug2: channel 0: request env confirm 0
debug3: Ignored env _
debug3: Ignored env OLDPWD
debug2: channel 0: request shell confirm 1
debug2: callback done
debug2: channel 0: open confirm rwindow 32000 rmax 35000
debug2: channel_input_status_confirm: type 100 id 0
PTY allocation request failed on channel 0
debug2: channel_input_status_confirm: type 99 id 0
debug2: shell request accepted on channel 0
debug2: channel 0: rcvd ext data 90
Hi acandael! You've successfully authenticated, but GitHub does not provide shell access.
debug2: channel 0: written 90 to efd 7
debug1: client_input_channel_req: channel 0 rtype exit-status reply 0
debug2: channel 0: rcvd eof
debug2: channel 0: output open -> drain
debug2: channel 0: obuf empty
debug2: channel 0: close_write
debug2: channel 0: output drain -> closed
debug2: channel 0: rcvd close
debug2: channel 0: close_read
debug2: channel 0: input open -> closed
debug3: channel 0: will not send data after close
debug2: channel 0: almost dead
debug2: channel 0: gc: notify user
debug2: channel 0: gc: user detached
debug2: channel 0: send close
debug2: channel 0: is dead
debug2: channel 0: garbage collecting
debug1: channel 0: free: client-session, nchannels 1
debug3: channel 0: status: The following connections are open:
#0 client-session (t4 r43 i3/0 o3/0 fd -1/-1 cc -1)
Connection to github.com closed.
Transferred: sent 3448, received 1976 bytes, in 0.2 seconds
Bytes per second: sent 15214.0, received 8718.9
debug1: Exit status 1
That error looks like it is coming from git. Are you able to access the repository directly with git?