RunAs Administrator returning "SYSTEM" as $env:USERNAME in PowerShell

[mpearon]

Windows Terminal version

1.19.2682.0

Windows build number

10.0.22621.0

Other Software

Windows PowerShell 5.1.22621.2428
PowerShell 7.3.8

Steps to reproduce

Launch Terminal as Administrator (Win+X, A)
Issue the following:

$env:USERNAME

Expected Behavior

The username of the currently logged in user should be returned

Actual Behavior

SYSTEM is returned

The screenshot included shows PWSH 7.3.8 running outside Terminal (top left) and inside Terminal (top right) and Windows PowerShell 5.1 running outside Terminal (bottom left) and inside Terminal (bottom right).

The output of $env:USERNAME (which is the expected output) has been redacted in the screenshots and the prompt customized to prevent data leak - but this occurs with no customizations and with a fresh installation of Terminal from the Windows Store.

[mpearon]

I learned something about the $env: automatic variables.
I just assumed they were immutable, but they are not. I would like to see this change in behavior explained, but going forward, I guess I will use [System.Environment]::UserName, because that seems a lot safer.

[DHowett]

Do you use "over-the-shoulder" elevation (where you need to provide an admin username and password which is different from your main user)?

[237dmitry]

I could not reproduce:

[mpearon]

Do you use "over-the-shoulder" elevation (where you need to provide an admin username and password which is different from your main user)?

@DHowett - I'm leveraging Win+X, A - which triggers UAC. At that prompt, I'm providing a credential that is different than my logged in user.

I could not reproduce:

@237dmitry - Terminal version 1.19.2682.0? Leave it to me to have the weird issue.

[DHowett]

I'm providing a credential that is different than my logged in user.

So, I think it might be because of this. "Over-the-shoulder" elevation is slightly different from the normal split-token kind of elevation that most folks use.

If you launch PowerShell directly as admin, without terminal (Win+R, pwsh, Ctrl+Shift+Enter), do you see the same thing?

[237dmitry]

Terminal version 1.19.2682.0

No, I updated WT to 1.19.2831.0 with msixbundle from release page, but I do not remember such behavior.

[mpearon]

I'm providing a credential that is different than my logged in user.

So, I think it might be because of this. "Over-the-shoulder" elevation is slightly different from the normal split-token kind of elevation that most folks use.

If you launch PowerShell directly as admin, without terminal (Win+R, pwsh, Ctrl+Shift+Enter), do you see the same thing?

@DHowett - No. This is what my screenshot is demonstrating (left side is launching PowerShell outside of Terminal). This issue only occurs when Terminal is in play.