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SFTP Connection fails with "permission denied" but I can connect using the sftp cli

See original GitHub issue

I am trying to connect to a client’s SFTP server using a username and password that they provided. When connecting using SSH.NET I get the error Renci.SshNet.Common.SftpPermissionDeniedException: permission denied thrown, but I can connect using the same username and password using the sftp cli binary and other sftp tools.

Any idea what to change on my end, or how to debug what is different between the two methods of access?

Thanks

Issue Analytics

State:
Created a year ago
Reactions:1
Comments:6

Top GitHub Comments

1reaction

devdotatbcommented, Nov 2, 2022

I also have same error ( key already changed to OpenSSH )

0reactions

maxfurmancommented, Nov 2, 2022

I cloned the repo locally, built in debug mode, and dumped out the logs. Here’s what I see:

Initiating connection to 'XXXXXX'.
Server version '2.0' on 'XXXXX'.
[] Received message 'KeyExchangeInitMessage' from server: 'SSH_MSG_KEXINIT'.
[] Sending message 'KeyExchangeInitMessage' to server: 'SSH_MSG_KEXINIT'.
[] Sending message 'KeyExchangeEcdhInitMessage' to server: 'SSH_MSG_KEX_ECDH_INIT'.
[] Received message 'KeyExchangeEcdhReplyMessage' from server: 'SSH_MSG_KEX_ECDH_REPLY'.
[] Sending message 'NewKeysMessage' to server: 'SSH_MSG_NEWKEYS'.
[] Received message 'NewKeysMessage' from server: 'SSH_MSG_NEWKEYS'.
[C106C1B8B8183B845214200E48F41B8E43976AC3B486AE84E71B6AD1348FE878] Creating server cipher (Name:aes256-ctr,Key:<long key removed>,IV:<long IV removed>)
[C106C1B8B8183B845214200E48F41B8E43976AC3B486AE84E71B6AD1348FE878] Sending message 'ServiceRequestMessage' to server: 'SSH_MSG_SERVICE_REQUEST'.
[C106C1B8B8183B845214200E48F41B8E43976AC3B486AE84E71B6AD1348FE878] Received message 'ServiceAcceptMessage' from server: 'SSH_MSG_SERVICE_ACCEPT'.
[C106C1B8B8183B845214200E48F41B8E43976AC3B486AE84E71B6AD1348FE878] Received message 'BannerMessage' from server: 'SSH_MSG_USERAUTH_BANNER'.
[C106C1B8B8183B845214200E48F41B8E43976AC3B486AE84E71B6AD1348FE878] Sending message 'RequestMessageNone' to server: 'SSH_MSG_USERAUTH_REQUEST'.
[C106C1B8B8183B845214200E48F41B8E43976AC3B486AE84E71B6AD1348FE878] Received message 'FailureMessage' from server: 'SSH_MSG_USERAUTH_FAILURE'.
[C106C1B8B8183B845214200E48F41B8E43976AC3B486AE84E71B6AD1348FE878] Sending message 'RequestMessagePassword' to server: 'SSH_MSG_USERAUTH_REQUEST'.
[C106C1B8B8183B845214200E48F41B8E43976AC3B486AE84E71B6AD1348FE878] Received message 'SuccessMessage' from server: 'SSH_MSG_USERAUTH_SUCCESS'.
[C106C1B8B8183B845214200E48F41B8E43976AC3B486AE84E71B6AD1348FE878] Sending message 'ChannelOpenMessage' to server: 'SSH_MSG_CHANNEL_OPEN'.
[C106C1B8B8183B845214200E48F41B8E43976AC3B486AE84E71B6AD1348FE878] Received message 'ChannelOpenConfirmationMessage' from server: 'SSH_MSG_CHANNEL_OPEN_CONFIRMATION : #0'.
[C106C1B8B8183B845214200E48F41B8E43976AC3B486AE84E71B6AD1348FE878] Sending message 'ChannelRequestMessage' to server: 'SSH_MSG_CHANNEL_REQUEST : #0'.
[C106C1B8B8183B845214200E48F41B8E43976AC3B486AE84E71B6AD1348FE878] Received message 'ChannelWindowAdjustMessage' from server: 'SSH_MSG_CHANNEL_WINDOW_ADJUST : #0'.
[C106C1B8B8183B845214200E48F41B8E43976AC3B486AE84E71B6AD1348FE878] Received message 'ChannelSuccessMessage' from server: 'SSH_MSG_CHANNEL_SUCCESS : #0'.
[C106C1B8B8183B845214200E48F41B8E43976AC3B486AE84E71B6AD1348FE878] Sending message 'ChannelDataMessage' to server: 'SSH_MSG_CHANNEL_DATA : #0'.
[C106C1B8B8183B845214200E48F41B8E43976AC3B486AE84E71B6AD1348FE878] Received message 'ChannelDataMessage' from server: 'SSH_MSG_CHANNEL_DATA : #0'.
[C106C1B8B8183B845214200E48F41B8E43976AC3B486AE84E71B6AD1348FE878] Sending message 'ChannelDataMessage' to server: 'SSH_MSG_CHANNEL_DATA : #0'.
[C106C1B8B8183B845214200E48F41B8E43976AC3B486AE84E71B6AD1348FE878] Received message 'ChannelDataMessage' from server: 'SSH_MSG_CHANNEL_DATA : #0'.
[C106C1B8B8183B845214200E48F41B8E43976AC3B486AE84E71B6AD1348FE878] Sending message 'ChannelDataMessage' to server: 'SSH_MSG_CHANNEL_DATA : #0'.
[C106C1B8B8183B845214200E48F41B8E43976AC3B486AE84E71B6AD1348FE878] Received message 'ChannelDataMessage' from server: 'SSH_MSG_CHANNEL_DATA : #0'.
[C106C1B8B8183B845214200E48F41B8E43976AC3B486AE84E71B6AD1348FE878] Sending message 'ChannelDataMessage' to server: 'SSH_MSG_CHANNEL_DATA : #0'.
[C106C1B8B8183B845214200E48F41B8E43976AC3B486AE84E71B6AD1348FE878] Received message 'ChannelDataMessage' from server: 'SSH_MSG_CHANNEL_DATA : #0'.
10:58:34 Program FATAL Error: Renci.SshNet.Common.SftpPermissionDeniedException: permission denied

It appears to successfully create the session and exchange data. I can’t figure out why these requests are denied and requests with the same username and password from the same server using the sftp builtin are permitted.