Does any one how to tell what folders are trusted when the ExecutionPolicy is set to RemotedSigned? I want to run a number of Powershell script of our network share (which is not mapped, hence using the full unc), but i do not want to have to digitally signed them all.
Any help would be great.
Thanks.
We have done this in the past by adding a registry key under HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\ZoneMap\EscDomains that names the server where the share resides. Under the EscDomains key, add a key that is the server name. Under that key, add a DWORD value with the name "file" and the value 2.
You need to do this on each machine that will run scripts from the server, but you can do that via group policy. There are security implications to this beyond running PowerShell scripts. I don't know if this will work if your computers are not in a domain. If there are better solutions, I look forward to learning about them.
For more information, see this KB article.
So, what happens when you run a script from UNC Path?
With RemoteSigned, you should be able to run all scripts written & run locally without a digital signature.
RemoteSigned
- Scripts can run.
- Requires a digital signature from a trusted
publisher on scripts and configuration files that
are downloaded from the Internet (including
e-mail and instant messaging programs).
- Does not require digital signatures on scripts that you have run
and that you have written on the local computer (not
downloaded from the Internet).
- Risks running unsigned scripts from sources other
than the Internet and signed, but malicious, scripts.
Unrestricted
- Unsigned scripts can run. (This risks running malicious
scripts.)
- Warns the user before running srcipts and configuration
files that are downloaded from the Internet.
Related
I've been having issues with people modifying powershell scripts and causing mayhem. Is there a one liner that I can insert into a current script to require a password that I set in order to modify the script? I still need everyone to be able to run it.
The easiest and most straightforward way is to put the scripts somewhere that the problem users don't have write access to. There's nothing you can do in the language itself to prevent a user from modifying a file they have write access to.
If you can't do this for some reason (they are admins and have too much access), then you can do a few other things.
Signing
Apply a digital signature to your scripts.
For this to work, you need to be able to enforce an execution policy of AllSigned (or RemoteSigned if these scripts are executed directly off of a share). You might do this with Group Policy.
You also need to control access to the signing certificate and ensure that it's the only one that's trusted.
Note that these users can still copy the script locally, make modifications, run powershell.exe -ExecutionPolicy Bypass and still run their modified script.
The difference is that this is their copy and doesn't break it for anyone else. And if they overwrite the central script without signing it or signing it with an untrusted certificate then everyone will notice.
If the users are privileged enough they be able to override more of this.
Central Deployment
Put the scripts in a custom local repository and use the package management functions Find-Script / Install-Script so everyone is referring to the same ones, and have a well-thought out deployment process. This can be combined with signing.
But...
Ultimately if these users are privileged and they are acting in bad faith, this is a personnel problem and can't effectively be solved with technology. In that case, The Workplace may be able to help.
I am trying to sign a simple script to show my students. When I sign the script, which I created in Notepad, I get an unknown error using Set-AuthicodeSignature. When I look at the script after trying to sign in Notepad is shows a signature block. When I try to run it says the PowerShell says the script is not signed. I am using an executionpolicy of AllSigned. Any suggestions? The script runs fine if I set the executionpolicy of Unrestricted.
For the error in Set-AuthenticodeSignature, Chances are your character encoding is not in UTF-8. You can change the character encoding to UTF-8 within notepad and things will work just fine. This is the most common cause of the "unknown error"
Regarding the next issue, of getting the script to run. From Get-Help about_Execution_Policies the AllSigned policy:
- Scripts can run.
- Requires that all scripts and configuration files
be signed by a trusted publisher, including scripts
that you write on the local computer.
We have a couple of options here. We could trust the certificate that we created at a higher level (by adding it to a trusted store), we can use a different certificate from a root CA, also trusted at a higher level and lastly, we could use a different ExecutionPolicy. Also from Get-Help about_Execution_Policies you may want to try using "RemoteSigned" as that will allow you to run self-signed scripts you wrote on your own machine, as well as trusted scripts downloaded from the internet:
RemoteSigned
- Scripts can run. This is the default execution
policy in Windows Server 2012 R2.
- Requires a digital signature from a trusted
publisher on scripts and configuration files that
are downloaded from the Internet (including
e-mail and instant messaging programs).
- Does not require digital signatures on scripts that
you have written on the local computer (not
downloaded from the Internet).
- Runs scripts that are downloaded from the Internet
and not signed, if the scripts are unblocked, such
as by using the Unblock-File cmdlet.
- Risks running unsigned scripts from sources other
than the Internet and signed, but malicious, scripts.
We have purchased Thawte code signing certificate and am able to sign scripts with that. In all signed execution policy mode, powershell still asks for confirmation on servers before running the code. I need to run this code as scheduled job on many servers and was wondering if their is any workaround this.
In my search it seems like that the certificate needs to be in trusted publisher before execution of scripts. I could not find any scripts that can place certificate in TrustedPublisher on a remote server.
Thank you for all the help you can provide.
PowerShell Help about execution policies easily found by PS C:\>help about_Execution_Policies shows that in AllSigned mode it will Prompt you before running scripts from Publishers that you have not yet classified as trusted or untrusted. You can try RemoteSigned or try this wonderfully explainedby Scott Hanselman http://www.hanselman.com/blog/SigningPowerShellScripts.aspx
Signed scripts can be transported by exporting (from original
computer) and importing (to the new computer) the Powershell
certificates found in the Trusted Root Certification Authorities
container. Optionally, the Trusted Publishers can also be moved to
prevent the first-time prompt.
Final note on the blog
Note that Powershell will prompt you the first time it’s run unless
you also import the Trusted Publishers certificate.
I'm creating and testing some powershell scripts to do some basic file copying. I've set my executionpolicy to RemoteSigned. According to the help, this should allow me to run scripts that were not downloaded from the internet. However, my observations seem to indicate that this will run only scripts created on the local machine.
For instance, if I create a script on my development machine and try to copy to my server (on my same domain), the script will not run. However, if I open up the Powershell ISE on the server and open my script, copy the code and paste it into a new file window and save it to the server, the script then runs. Further, if I want to create a self-signed certificate, it will not run on other computers (per the help).
So, this all seems a bit cumbersome that I have to develop my scripts on the machine they are to be run or go through the copy/paste routine mentioned above to get them to run on my server. I just want to know that I've understood all of this correctly and there is no other way to create a script within the same domain and run it under the remotesigned execution policy without paying the fee for a certificate.
this post here provide the method for executing script from shared folder. hope this could help you :-)
I am DBA. I am trying to write bunch of scripts that I could execute from one central server. Ideal would be to send all the scripts from central server to say 50+ servers across multiple win domains (for databases management purposes).
The problem I am running into is - security. Seems like PowerShell Remoting is the way to go. But when I send a script to another server, I get 'not digitally signed' error.
I could 'self sign'. But that cert if only trusted on local machine. So that option is out.
Maybe Certificate Authority is a way to go. Or adding trusted hosts. I just have no clue on this one, so if you know any blog posts or how to do this - it would be big help.
Well, it's a security risk, but there's always the possibility of setting the execution policy to RemoteSigned, keeping a local repository on each server and calling those as needed via PS-Remoting. I don't like that idea one bit though.
If you are doing remote execution, you will need to sign your scripts. A detailed step by step can be found here. It even covers deploying the cert via GPO so that it's domain trusted.
I would use PowerShell remoting. This would allow you to run it as remote commands instead of remote scripts. If you catch the bottom of this SimpleTalk article, after "Persistent Sessions". It shows the option of executing a set of commands against each server instead of the script. This should prevent having to deal with the remote signed issue and provide a little more control.
The only thing to deal with on remote sessions is your credentials. I have not tried this on multiple domains but a few stand-alone servers.