Lenovo's system update program can be started without administrator right. When the service starts, it creates a temporary administrator account to perform the installation.
Why can a windows application have right to create an administrator-level account? How can I achieve it when I want to create a similar program?
It's related to TVSU. A design point of TVSU is that even limited users can install updates from Lenovo. And to accomplish this, the TVSU service creates a temporary admin account with a randomized username and password, then uses it to do the installations on behalf of the limited user. This is the only time the account is created. The account is not created when an admin user does updates, because the admin user already has the permissions needed to do installations.
The account is supposed to be deleted after the TVSU session finishes, but I'm aware of a case where this doesn't happen and the account stays around. However there isn't any security risk to this because both the account and password are random and not known by anything except the specific TVSU process that created them, and this process ended the last time TVSU was closed. You can safely ignore the account, delete the account, or else it should be deleted the next time TVSU is run.
Related
I am running this in Windows 10
What is the difference between running a program in a user account with admin rights, versus running in a standard account but right clicking and running as admin - and by difference, I mean from the program's point of view.
I thought from the program's point of view, there would be no difference. But apparently that isn't exactly true.
See - I have this piece of hardware (The DLink Air Bridge for the Quest 2 Headset). It won't connect to the desktop app unless I run it in an account with admin rights. But here is the thing, if I run it in the same account (but now with only standard rights) but right click on the program and "Run as Admin" - it still won't connect. How can this be?
I am asking this here because the support for both Meta and Dlink is hopelessly, HILARIOUSLY inept.
Also - what is worse when it comes to security: Using an account for daily stuff with admin rights, or right clicking on particular programs that need it and always running as an admin. I assumed it was the latter - but I am an idiot when it comes to computer security.
When an administrator logs in, the full elevated token is stored in a system process and a more restricted token is generated from this and is used to start Explorer.exe at logon.
When this admin user elevates, UAC starts the new process with the full elevated token (often called "split token"). This causes some minor complications related to mapped network drives and HKCU COM objects but essentially the two tokens refer to the same user account and the same HKCU registry key.
On the other hand, when a non-admin UAC elevates they have to enter the credentials of an administrator and it is this administrator and their account/profile/HKCU that is tied to the token when the new process is started. Meaning, a process running as this administrator is present in the desktop session of the non-admin user. This means a different profile folder and different HKCU compared to other processes in the session.
According to Microsoft, UAC is not a security boundary. If you are really concerned about security then you need to log in as the administrator separately.
After adding a user to the local Administrators group... even though the user is in the local group, they still don't have effective permissions as a desktop Administrator. They have to at least logoff/logon or reboot for the permissions to take effect. I was wondering if there's a way to do this via command-line in a seamless fashion.
This resource:
http://woshub.com/how-to-refresh-ad-groups-membership-without-user-logoff/
says, you can use:
klist -li 0:0x3e7 purge
However, after I ran that command, it didn't make any difference; I still had to logoff/logon or reboot for effective permissions to take place.
There are two things in play here:
What the local machine thinks your privileges are
What other machines think your privileges are when you connect to them
Purging the ticket cache with klist purge will remove your user ticket cache. This will affect (2), in that when you go try and communicate with another service you must first get a new TGT, which is the thing that actually contains your group membership information. This is why your membership information is cached for 'a while', i.e. because the TGT sticks around for a while, and when you ask for a ticket to another service, the Domain Controller literally just copies the contents of the TGT to the newly requested ticket, and that TGT can exist for a week or more.
Getting a new TGT will always return exactly what the DC thinks your membership is.
Affecting (1) is more complicated. Windows stores this information in what's called an NT Token, which is immutable for the lifetime of a logon session. The NT Token gets your group membership during logon. Windows asks the DC for that information, and copies it into the NT Token on receipt. This is why it appears as though your membership doesn't change, that is, because Windows hasn't gone off to get your new membership information and hasn't refreshed your NT Token (because it can't, because it's immutable).
As it happens though, a logon session is not forever, and actually only exists between session unlocks. Your membership information will get refreshed shortly after a lock/unlock once it communicates with DC.
0x3e7 is the ID of the SYSTEM account, not the user you are trying to manage. Issue just klist to get the ID of your currently logged on user. You can issue just:
klist purge
to delete the cached kerberos tickets of the currently logged on user. After that, just access a ressource where you need a kerberos ticket (e. g. a network share) and you will get new cached kerberos tickets automatically. If you don't have a particular network share, access the default share of your domain (just your domain name): \\mydomain.com
If time does not matter and you just do not want to login again, you can wait at most 10 hours. That's the default time span, after which a kerberos ticket will automatically be renewed.
All,
I have no idea how Windows service works, just curious when we register a windows service(such as auto run a server after reboot), if it requires a user profile to load info(such as pulling data from somewhere else), what user profile does it load?
Thanks,
You can select what user run each service registered and the system comes with users assigned per service. The most used by the system is SYSTEM.
To check this you have to:
Go to services.
Right click on the desired service and properties.
Go to the Log on tab and check.
If the Local System account is selected the username is SYSTEM which has special permissions on almost all folder and Windows sections including users' profiles data.
By the other hand if you would like to do something special with an specific account you can tell the system the service will start with the account specified. Just make sure to update the password information every time the user change it.
Regards,
Luis
(Skip to the bottom for the TLDR version.)
OK - so I have searched (really!) and all other UAC articles I have found seem to center on enabling, disabling, detecting or hiding UAC. My issue is not one of those, so here goes:
My user used to have the standard dual-token setup where I was in the Administrators group and the UAC's Consent UI would just ask me if I wanted to proceed. Now, we have separate administrative-level accounts that we need to use, and I have to authenticate with this new user. The problem I am having is that previously, starting an app as Administrator just elevated my current user, where now if I use the credentials of the new administrative user, whatever I am running runs AS that new user.
As an example, previously elevating CMD and typing whoami into the command prompt used to return my normal/current user, where it now returns the new administrative user.
This has serious negative consequences - since this is a new user, and an Administrative-level one, if any files are created using this new user, my normal user cannot write to or delete them unless I manually adjust permissions and ownership. If I use my development environment under the new account (e.g. I need to debug a service or work with a driver) and rebuild something, I end up with a bunch of files that I cannot manipulate unless I am an administrator. Likewise if I add a file while running as this new account - my SCM tool will not be able to update that file later unless it also runs under this new administrative account.
Also, Since a profile is associated with this user, things run under a completely different environment (different %USERNAME%, %USERPROFILE%, %LOCALAPPDATA%, etc.)
Installing an application will also work incorrectly if it is installed just for the current user (e.g. the "Just Me" option), instead of for all users. Things that are licensed to/in my normal user account also fail to function if run under the new account, because things are running as that new user.
The ripple effects of this change are getting larger and larger the more I work with it. So...
[TLDR] Is there a way to get temporary elevation of the current user without that user having the normal dual-token setup you get from being in the Administrative group? Or are you stuck with the impersonation behavior?
First of all, I realize this is a messy situation, but it's not of my design, and I'm just trying to help, and for that I need your help.
App A is getting installed automatically via SMS installer under the Administrator account, not the PC owner's User account. App A has a registry key defined in HKEY_LOCAL_MACHINE hive.
After App A is installed, we want to edit the above mentioned registry key, to assign the User's C:\Users\USER_ID\Documents\ folder (I'm told we don't don't know who the user is and don't have access to USER_ID during step 1).
I know all about UAC, Application Manifest, and requestedExecutionLevel. However, I'm told we can't expect that all users will be in the Administrators group on their machine.
Solution must be backwards compatible with Windows XP as well.
I'm searching for options to get `C:\Users\USER_ID\Documents\' into the 'HKEY_LOCAL_MACHINE' hive under the above listed conditions.
I found this thread that might be related to a similar situation, but I don't fully understand it yet (so I will give credit to anyone that explain it better):
Find out (read) logged in user in a cmd started as a different user
I also read something that rules out ClickOnce:
Clickonce + HKEY_LOCAL_MACHINE
After App A is installed with admin privileges you are trying to run an additional script as the local user who does not have admin privileges . In order for your secondary script to write to the local machine key it will have to be run with administrative privileges ..period. That said, you have basically two choices:
1) Use the RunAs command to run the script with elevated privileges and have the user type in a admin username and password to run the script with elevated privileges.
2) This is the better way imo - Since SMS is being leveraged as the delivery tool, use its capability to detect and use local client configuration settings to write the key at the time of installation.
So basically the SMS package would have to be setup to run only when the local user logs on one time so that SMS can grab the current user and write it to a file somewhere.. after that is completed SMS can run a separate package as the admin (user will get prompted) to do the software install looking for the file containing the user and then consequently updating the local machine key to the correct user my document path.
Enjoy!