How do you run CMD.exe under the Local System Account? - windows-services

I'm currently running Vista and I would like to manually complete the same operations as my Windows Service. Since the Windows Service is running under the Local System Account, I would like to emulate this same behavior. Basically, I would like to run CMD.EXE under the Local System Account.
I found information online which suggests lauching the CMD.exe using the DOS Task Scheduler AT command, but I received a Vista warning that "due to security enhancements, this task will run at the time excepted but not interactively." Here's a sample command:
AT 12:00 /interactive cmd.exe
Another solution suggested creating a secondary Windows Service via the Service Control (sc.exe) which merely launches CMD.exe.
C:\sc create RunCMDAsLSA binpath= "cmd" type=own type=interact
C:\sc start RunCMDAsLSA
In this case the service fails to start and results it the following error message:
FAILED 1053: The service did not respond to the start or control request in a timely fashion.
The third suggestion was to launch CMD.exe via a Scheduled Task. Though you may run scheduled tasks under various accounts, I don't believe the Local System Account is one of them.
I've tried using the Runas as well, but think I'm running into the same restriction as found when running a scheduled task.
Thus far, each of my attempts have ended in failure. Any suggestions?

Though I haven't personally tested, I have good reason to believe that the above stated AT COMMAND solution will work for XP, 2000 and Server 2003. Per my and Bryant's testing, we've identified that the same approach does not work with Vista or Windows Server 2008 -- most probably due to added security and the /interactive switch being deprecated.
However, I came across this article which demonstrates the use of PSTools from SysInternals (which was acquired by Microsoft in July, 2006.) I launched the command line via the following and suddenly I was running under the Local Admin Account like magic:
psexec -i -s cmd.exe
PSTools works well. It's a lightweight, well-documented set of tools which provides an appropriate solution to my problem.
Many thanks to those who offered help.

Download psexec.exe from Sysinternals.
Place it in your C:\ drive.
Logon as a standard or admin user and use the following command: cd \. This places you in the root directory of your drive, where psexec is located.
Use the following command: psexec -i -s cmd.exe where -i is for interactive and -s is for system account.
When the command completes, a cmd shell will be launched. Type whoami; it will say 'system"
Open taskmanager. Kill explorer.exe.
From an elevated command shell type start explorer.exe.
When explorer is launched notice the name "system" in start menu bar. Now you can delete some files in system32 directory which as admin you can't delete or as admin you would have to try hard to change permissions to delete those files.
Users who try to rename or deleate System files in any protected directory of windows should know that all windows files are protected by DACLS while renaming a file you have to change the owner and replace TrustedInstaller which owns the file and make any user like a user who belongs to administrator group as owner of file then try to rename it after changing the permission, it will work and while you are running windows explorer with kernel privilages you are somewhat limited in terms of Network access for security reasons and it is still a research topic for me to get access back

Found an answer here which seems to solve the problem by adding /k start to the binPath parameter. So that would give you:
sc create testsvc binpath= "cmd /K start" type= own type= interact
However, Ben said that didn't work for him and when I tried it on Windows Server 2008 it did create the cmd.exe process under local system, but it wasn't interactive (I couldn't see the window).
I don't think there is an easy way to do what you ask, but I'm wondering why you're doing it at all? Are you just trying to see what is happening when you run your service? Seems like you could just use logging to determine what is happening instead of having to run the exe as local system...

Using Secure Desktop to run cmd.exe as system
We can get kernel access through CMD in Windows XP/Vista/7/8.1 easily by attaching a debugger:
REG ADD "HKLM\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Image File Execution Options\osk.exe" /v Debugger /t REG_SZ /d "C:\windows\system32\cmd.exe"
Run CMD as Administrator
Then use this command in Elevated:
CMD REG ADD "HKLM\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Image File Execution Options\osk.exe" /v Debugger /t REG_SZ /d "C:\windows\system32\cmd.exe"
Then run osk (onscreenkeyboard). It still does not run with system Integrity level if you check through process explorer, but if you can use OSK in service session, it will run as NT Authority\SYSTEM
so I had the idea you have to run it on Secure Desktop.
Start any file as Administrator. When UAC prompts appear, just press Win+U and start OSK and it will start CMD instead. Then in the elevated prompt, type whoami and you will get NT Authority\System. After that, you can start Explorer from the system command shell and use the System profile, but you are somewhat limited what you can do on the network through SYSTEM privileges for security reasons. I will add more explanation later as I discovered it a year ago.
A Brief Explanation of how this happens
Running Cmd.exe Under Local System Account Without Using PsExec. This method runs Debugger Trap technique that was discovered earlier, well this technique has its own benefits it can be used to trap some crafty/malicious worm or malware in the debugger and run some other exe instead to stop the spread or damage temporary. here this registry key traps onscreen keyboard in windows native debugger and runs cmd.exe instead but cmd will still run with Logged on users privileges, however if we run cmd in session0 we can get system shell. so we add here another idea we span the cmd on secure desktop remember secure desktop runs in session 0 under system account and we get system shell. So whenever you run anything as elevated, you have to answer the UAC prompt and UAC prompts on dark, non interactive desktop and once you see it you have to press Win+U and then select OSK you will get CMD.exe running under Local system privileges. There are even more ways to get local system access with CMD

an alternative to this is Process hacker if you go into run as... (Interactive doesnt work for people with the security enhancments but that wont matter) and when box opens put Service into
the box type and put SYSTEM into user box and put C:\Users\Windows\system32\cmd.exe leave the rest click ok and boch you have got a window with cmd on it and run as system now do the other steps for yourself because im suggesting you know them

There is another way. There is a program called PowerRun which allows for elevated cmd to be run. Even with TrustedInstaller rights. It allows for both console and GUI commands.

(Comment)
I can't comment yet, so posting here... I just tried the above OSK.EXE debug trick but regedit instantly closes when I save the filled "C:\windows\system32\cmd.exe" into the already created Debugger key so Microsoft is actively working to block native ways to do this. It is really weird because other things do not trigger this.
Using task scheduler does create a SYSTEM CMD but it is in the system environment and not displayed within a human user profile so this is also now defunct (though it is logical).
Currently on Microsoft Windows [Version 10.0.20201.1000]
So, at this point it has to be third party software that mediates this and further tricks are being more actively sealed by Microsoft these days.

if you can write a batch file that does not need to be interactive, try running that batch file as a service, to do what needs to be done.

I use the RunAsTi utility to run as TrustedInstaller (high privilege). The utility can be used even in recovery mode of Windows (the mode you enter by doing Shift+Restart), the psexec utility doesn't work there. But you need to add your C:\Windows and C:\Windows\System32 (not X:\Windows and X:\Windows\System32) paths to the PATH environment variable, otherwise RunAsTi won't work in recovery mode, it will just print: AdjustTokenPrivileges for SeImpersonateName: Not all privileges or groups referenced are assigned to the caller.

Using task scheduler, schedule a run of CMDKEY running under SYSTEM with the appropriate arguments of /add: /user: and /pass:
No need to install anything.

i used Paul Harris recommendation and created a batch file .cmd or .bat with what ever command i needed to run under system and used the schedule task run one time.
than trigger it as needed. and updated the batch as needed. so any command i need to run under system i just update the batch.

Related

Install Chocolatey using TFS build

I would like to silently install chocolatey on a series of test agents, and I'm trying to use a TFS build to do so. I have a build step that uses the "Run Powershell on Remote Machines" task. This in turn invokes the ps1 to install chocolatey, from https://chocolatey.org/install.ps1, and I supply the powershell switches as documented on the chocolatey website:
-NoProfile -InputFormat None -ExecutionPolicy Bypass
When I run the build, I receive this error:
System.Management.Automation.RuntimeException: A command that prompts the user failed because the host program or the command type does not support user interaction. Try a host program that supports user interaction, such as the Windows PowerShell Console or Windows PowerShell ISE, and remove prompt-related commands from command types that do not support user interaction, such as Windows PowerShell workflows. ---> System.Management.Automation.RuntimeException: A command that prompts the user failed because the host program or the command type does not support user interaction. Try a host program that supports user interaction, such as the Windows PowerShell Console or Windows PowerShell ISE, and remove prompt-related commands from command types that do not support user interaction, such as Windows PowerShell workflows.
What am I doing wrong? Seems odd that the chocolatey installer required user interaction, I think the whole point of chocolately was silent installs?
It seems you have wrong settings in task "PowerShell on Target Machines". Follow the steps below:
Create a .ps1 file on the target machine and specify the text below:
Set-ExecutionPolicy Bypass -Scope Process -Force; iex ((New-Object
System.Net.WebClient).DownloadString('https://chocolatey.org/install.ps1'))
In "PowerShell on Target Machines" task, specify the location of the .ps1 file just created.
Queue the build.
Check the screenshot below:
What am I doing wrong? Seems odd that the chocolatey installer
required user interaction, I think the whole point of chocolately was
silent installs?
Typically it goes fully silent, unless there is something (like a proxy) that requires input. It would be best to determine what might be causing the issue by running the install directly on the machine and seeing what happens.
Details
The install.ps1 passes over to chocolateyInstall.ps1, which calls chocolateySetup.psm1.
As you look over that script, you may notice that the install.ps1 uses Write-Output, but that psm1 uses Write-Host in some places. This may or may not cause issues, but it's unlikely given that the script works fine with PowerShell DSC.
So it could be a few things:
Make sure whatever runs that script has Administrator privileges, otherwise you will get an access denied error (unless you specify a different Chocolatey installation location).
Make sure you are not getting hit by needing to put in proxy credentials (which is fixed by the Offline Recommendation below).
Make sure you are not getting hit with not being able to access internet resources (which is also fixed by using offline resources).
It could be something else causing a popup, like needing to install .NET 4.x. Recommend you have the latest .NET Framework in the 4.x series installed prior to installing Chocolatey.
Offline Recommendation
The best recommendation we can give - don't use the internet for any part of this script. If you want reliability, you should have everything internal. That includes the install.ps1 script you are going to use for Chocolatey and the chocolatey.nupkg itself.
Take a read over at https://chocolatey.org/install#completely-offline-install to understand our recommendations.

Cannot Open Devcon

I installed WinDDK 7600 in my Windows XP operating system.Now,when I double click the devcon.exe(Location- D:\WinDDK\7600.16385.1\tools\devcon\i386),the command prompt is just showing up and suddenly disappears.Can anyone resolve this issue.
As far as I'm aware devcon is a command-line only program. You have to run it from a command window (cmd.exe) with the appropriate parameters. Once you know the parameters you want to use, you can write a batch file to easily recreate the command you want.
I ran across this post because Win7 has a similar problem even when running in cmd.exe.
There is a solution found on Microsofts website here:
http://answers.microsoft.com/en-us/windows/forum/windows_7-hardware/devcon-not-working-correctly-in-windows-7/9abcc12c-d7db-4249-aec4-fc4ff0ea6ee8
I have not been able to verify it yet.
The same (a windows open and automatically close) happens even if using a normal command prompt. However opening the command prompt with administrator rights and then run devcon works.

PsExec gets stuck on licence prompt when running non-interactively

I have a Hudson build script which calls the SysInternals PsExec utility. Normally, when PsExec is run for the first time by a given user it pops up a dialog box asking the user to accept the licence. The build agent runs as a service and I can see that the build gets stuck at PsExec. Process Explorer shows that PsExec is running, so I strongly suspect it's displaying that same prompt, but because it's running non-interactively there is no way to accept the prompt. Is there any way to get around this silly limitation? Running on Windows Server 2008 R2 x64.
Use the /accepteula command-line switch to accept the licence agreement.
Or set
HKCU\Software\Sysinternals\PsExec\EulaAccepted
to 1
Caution: if the reg key above is set to 0 (EULA was declined once) then the /accepteula will not work, you have to set the key to 1 manually (or delete it altogether).
It's documented, but you have to use the 2003 version or higher.

Console Utility that can remote connect to other systems and issue commands

Frequenlty my work involves to VNC to a remote system and work on it. SInce i run command line apps on this remote system most of the time, i was wondering if there's an alternative software to command prompt which i could install on my local machine. Using this i should be able to create a session with the remote system and from then on all commands issued in command prompt should run in remote system.
localHost>dir --> should list the directory contents in remotehost active directory
localhost>app.exe should run app.exe in remote host and display its contents in localhost command prompt
I browsed a little and read about cmdlets in powershell. But it looks like i need to write a cmdlet for each app in the path (dir, mkdir, app.exe in the path). Correct me if am wrong. Once session is established, i simply need the commands invoked in local host to be run in the remote host and return the console output to local host. Please let me know if powershell + cmdlets are the only way
THanks
Just use PowerShell Remoting if it can be set up (requires a little preparation).
I'm not quite sure why you think of writing own cmdlets for stuff that's already there. dir is an alias to Get-ChildItem which does return the items in the current path (and—depending on options—some other stuff as well). And since PowerShell is a shell it has no problems running external programs too.
SSH is what you're looking for. Cygwin has a SSH server and client.
Unix people do this all the time with SSH. You can install the sshd server on your remote machine through Cygwin, then use PuTTY to connect to it.
As a bonus, PuTTY does not use the clunky Windows cmd.exe program; it's got a much nicer terminal of its own.
You could maybe even run PowerShell on the remote end, so you don't have to learn bash.
Depending upon on how you actuall access the machines PSExec may be an alternative that wont require you to install anything on the remote system.

Launching a service from msi installer that depends on assemblies installed by the msi

I'm using WiX to write a MSI installer to start a service that depends on DLLs installed by the MSI. On Vista, the DLLs become added to the global assembly cache in the MSI's InstallFinalize phase, so I can't use the built-in service starting command in WiX. That one tries to start the service before the DLLs are in the GAC, and fails. The solution seems to be to use a custom action instead [1], and run that after InstallFinalize.
The custom action I used was starting the service with sc. Everything works fine when running the installer as an administrator, but running as a regular user doesn't work. The installer will elevate privileges for the actual install phase, but will drop them after finalizing the installation, and starting the service with sc as a non-privileged user will fail. Setting the custom action to be deferred and no-impersonate to get admin privileges won't work either after InstallFinalize [2].
As a final kludge, I tried to add <Condition>Privileged</Condition> to the WiX file to tell the user that the installer needs to be run as Administrator, but I couldn't get that to work either. The Privileged value gets set to 1 during the installation, maybe when the main install sequence is given higher privileges.
So has anyone else ran into the combination of Vista, non-Administrator user, installer needs to start a service and service needs stuff that goes into GAC during installation to run? Is there any kind of working general approach to this?
[1] http://www.mail-archive.com/wix-users#lists.sourceforge.net/msg09162.html
[2] http://www.mail-archive.com/wix-users#lists.sourceforge.net/msg15381.html
This is one of those times when the easiest solution is just to schedule a reboot.
Here are a few possibilities :
If possible, do not install prerequisite assemblies in the GAC. This will allow your service to be started normally (ie between InstallInitialize and InstallFinalize).
Create a bootstrapper (a small app that launches prerequisite MSIs in a certain order). Place the prerequisite assemblies (those that go in the GAC) into their own MSI, and get the bootstrapper to install them before it installs your service.
Create a launcher (an even smaller app that just launches your MSI). Give it a manifest that will make it run elevated. That way, the entire MSI is elevated, not just the part that's between InstallInitialize and InstallFinalize. You should be able to invoke sc succesfully.
I agree with #sascha. Rebooting is not just the easiest but cleanest in this case. All of the other proposed solutions are going to set you up for a much higher failure rate in the future. IMHO, the Windows Installer design w.r.t. the GAC is busted. The reboot is recognition of that.

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