I am working on an app to pull information from a remote Linux system. I am using vb.net and the Renci.SshNet library.

Everything works fine until I have to run a command that requires sudo. When using powershell I just start the whole process with sudo -s then put in the password but sending the password after the sudo -s sommand with the Renci library does not seem to work.

Is there a way to send the password at the same time as the sudo -s command?

very unsafe:

ssh-keys is the std soln to this sort of requirement : eg https://www.cyberciti.biz/faq/how-to...on-linux-unix/

^ Unless they enable ssh root login I don't see how this has any bearing on OP's problem.

Unfortunately I know nothing of this Renci library or why it "does not seem to work".

A purely remote and sufficiently safe solution could be to allow this specific user to run this specific command in this specific scenario via a carefully crafted /etc/sudoers rule.

Well unless I misunderstood
That would require ssh-keys to login, although having to then sudo as well would be tricky..
I've never had to try that myself.

Usually either the caller had the root login key (for internal trusted system only), or the remote service acct can be logged into, so sudo wasn't necessary.

in that case I would rather try to set a passwordless sudo (post #4). Or use ssh key with sshd (post #5).
But what I don't understand exactly where do you need it? In your powershell session (in that case you can try to use "run as admin"), or on the remote linux box?

When I test this using Putty I am still prompted for password.

To address some of the other Comments/Questions

Renci is a library you can import into Visual Studio that provides SSH capability to your VB App.

The system I am trying to pull the information from will actually be many systems that are fielded all over the world. They are not connected to the internet or any external network for that matter. The end users have no admin access and in fact cannot even access the OS interface itself. The system boots to a custom GUI to control items on its closed network. There is a LAN port that is used to connect a laptop for configurations and updates.

We have a requirement to pull information (logs, system configuration information, etc) from the systems periodically to review. We do not want to provide admin access to these systems to the end users because they do not need that for their day to day operations. The only thing they will need admin access for is to pull this information so my thought was to send out a laptop to the sites that they can plug into that configuration port, log in, double click an icon on the desktop, let the app pull all the info it needs, then they send the laptop back. Before you say that is going to be costly, it is far more economical that putting someone on a plane to fly all over the world for 20 minutes of work at each site.

I know it is possible as there is an app that does what I want but it only pulls about half of what I need.

Modification of the Linux box is difficult as the vendor is hesitant to make any changes because "it works the way it is".

that is exactly the private/public key pair. Only the "owner" of this key will be allowed to do admin activities. There is no need to install additional software, only the official sshd required (and some configuration).
Otherwise it is still unclear how do you want to access that information from your windows host and why only the half of the data can be pulled.