RDM 2026.3.10.0 SSH Shell attempts SFTP when SFTP is disabled

Published 8 days ago

RDM 2026.3.10.0 64-bit on Windows is making a separate SFTP connection whenever I open an SSH Shell session, even though SFTP is completely disabled for the entry.

The target is a Keenetic router running KeeneticOS 5.01.C.6.0-1. Its SSH server provides the CLI but does not provide SFTP.

RDM SSH Shell settings:

Automatically open the file transfer tab: OFF
Show files in tree view: OFF
Show local files: OFF
All other SFTP options: OFF
SFTP toolbar button: OFF

The exported entry XML also confirms:
<ConnectionType>SSHShell</ConnectionType>
<ShowFilesInTreeView>false</ShowFilesInTreeView>
<ShowLocalFiles>false</ShowLocalFiles>There are no SFTP-specific properties in the entry.

I also tested:

enabling/disabling "Automatically open the file transfer tab" and reconnecting;
Open → Open (ignore specific settings);
a clean/global Sessions configuration with no SFTP settings.

The behaviour is unchanged.

Evidence
The normal SSH connection works correctly and reaches the Keenetic CLI:
User authenticated successfully using password method
Sending session channel open request
Received channel open confirmation
Sending pty request
Received channel success
Sending shell request
Received channel success
...
KeeneticOS version 5.01.C.6.0-1
(config)>

The ProtocolsSharp SSH log contains no SFTP subsystem request.

However, the Keenetic logs show a separate SSH connection immediately before the normal SSH session:
Child connection from 192.168.0.10:60193
Password authentication succeeded for 'user'@cli from 192.168.0.10:60193
Core::Authenticator: access to "sftp" denied for user "user".
Core::Session: client disconnected.

The normal SSH CLI connection then follows and works correctly.

So the issue appears to be that RDM is initialising an SFTP connection independently of the SSH Shell connection, despite SFTP being disabled.

Could you please confirm whether this is a known issue/regression in RDM 2026.3 and advise how to prevent the SFTP connection from being attempted?

<?xml version="1.0" encoding="utf-8"?>
<RDMExport>
<Connections>
<Connection>
<AppVersion>2026.3</AppVersion>
<ConnectionType>SSHShell</ConnectionType>
<ID>0000000-00000-0000-0000-000000000000</ID>
<Name>test</Name>
<OpenEmbedded>true</OpenEmbedded>
<Terminal>
<Host>192.168.0.1</Host>
<ShowFilesInTreeView>false</ShowFilesInTreeView>
<ShowLocalFiles>false</ShowLocalFiles>
</Terminal>
</Connection>
</Connections>
<DatabaseID>0000000-00000-0000-0000-000000000000</DatabaseID>
<Version>2</Version>
</RDMExport>

All Comments (2)

Jonathan Del Signore

Published 7 days ago

Hello,

I currently can't find anything on our end that would explain why an SFTP connection is attempted when the related settings are all turned off, but I might be missing something.

Can you confirm that this is an issue that started with 2026.3.x specifically, and that it wasn't happening before?

Also, would you mind testing the same connection with PuTTY and check if the same logs appear? That would help narrow it down.

Thank you

Jonathan Del Signore

markusher

Published 3 days ago

Hi Jonathan,

Thanks, the PuTTY test was the right call, and it clears RDM.

I repeated the test from the same PC against the same Keenetic router (now KeeneticOS 5.01.C.7.0-4), first with PuTTY 0.85 and then with Windows OpenSSH 9.5p2. Both produce exactly the same "sftp denied" message as RDM:

11:34:30 dropbear: Child connection from 192.168.0.10:64326 <- PuTTY
11:34:40 ndm: Core::Authenticator: user "user" authenticated, realm "Keenetic Peak", tag "cli".
11:34:40 dropbear: Password authentication succeeded for 'user'@cli from 192.168.0.10:64326
11:34:40 ndm: Core::Authenticator: access to "sftp" denied for user "user".
11:34:42 ndm: Core::Session: client disconnected.
11:34:42 ndm: Core::Authenticator: "user" logged in, SSH authenticated.
11:34:51 dropbear: Exit (user) from <192.168.0.10:64326>: Exited normally

11:35:09 dropbear: Child connection from 192.168.0.10:52602 <- Windows OpenSSH
11:35:22 ndm: Core::Authenticator: access to "sftp" denied for user "user".
11:35:23 ndm: Core::Session: client disconnected.
11:35:23 ndm: Core::Authenticator: "user" logged in, SSH authenticated.
11:35:31 dropbear: Exit (user) from <192.168.0.10:52602>: Disconnect received

The source port is the same throughout each session, so this isn't a separate connection. I misread the log in my first post. The "sftp denied" and "client disconnected" lines are KeeneticOS's own internal permission check during every SSH login, regardless of the client. They're not caused by an SFTP request from RDM.

On your version question: the router logs show the same message from RDM 2026.3.8, 3.10 and 3.12, and my logs don't go back far enough to cover 2026.2.

Sorry for the false alarm. Please close this as not an RDM issue. I'll take it up with Keenetic.

Thanks,
Mark