diff --git a/windows/security/application-security/application-control/user-account-control/how-it-works.md b/windows/security/application-security/application-control/user-account-control/how-it-works.md index 27338890ca..628efba7cf 100644 --- a/windows/security/application-security/application-control/user-account-control/how-it-works.md +++ b/windows/security/application-security/application-control/user-account-control/how-it-works.md @@ -1,8 +1,8 @@ --- -title: How User Account Control works +title: How User Account Control works description: Learn about User Account Control (UAC) components and how it interacts with the end users. ms.topic: concept-article -ms.date: 05/24/2023 +ms.date: 03/26/2024 --- # How User Account Control works @@ -26,7 +26,7 @@ To better understand how this process works, let's take a closer look at the Win The following diagram shows how the sign in process for an administrator differs from the sign in process for a standard user. -:::image type="content" source="images/uac-windows-logon-process.gif" alt-text="Diagram that describes the UAC Windows logon process."::: +:::image type="content" source="images/uac-windows-logon-process.gif" alt-text="Diagram that describes the UAC Windows sign-in process."::: By default, both standard and administrator users access resources and execute apps in the security context of a standard user.\ When a user signs in, the system creates an access token for that user. The access token contains information about the level of access that the user is granted, including specific security identifiers (SIDs) and Windows privileges. @@ -91,9 +91,9 @@ The elevation process is further secured by directing the prompt to the *secure When an executable file requests elevation, the *interactive desktop*, also called the *user desktop*, is switched to the secure desktop. The secure desktop dims the user desktop and displays an elevation prompt that must be responded to before continuing. When the user selects **Yes** or **No**, the desktop switches back to the user desktop. > [!NOTE] -> Starting in **Windows Server 2019**, it's not possible to paste the content of the clipboard on the secure desktop. This is the same behavior of the currently supported Windows client OS versions. +> Starting in **Windows Server 2019**, it's not possible to paste the content of the clipboard on the secure desktop. This is the same behavior of the currently supported Windows client OS versions. -Malware can present an imitation of the secure desktop, but when the **User Account Control: Behavior of the elevation prompt for administrators in Admin Approval Mode** policy setting is set to **Prompt for consent**, the malware doesn't gain elevation if the user selects **Yes** on the imitation. If the policy setting is set to **Prompt for credentials**, malware imitating the credential prompt may be able to gather the credentials from the user. However, the malware doesn't gain elevated privilege and the system has other protections that mitigate malware from taking control of the user interface even with a harvested password. +Malware can present an imitation of the secure desktop, but when the **User Account Control: Behavior of the elevation prompt for administrators in Admin Approval Mode** policy setting is set to **Prompt for consent**, the malware doesn't gain elevation if the user selects **Yes** on the imitation. If the policy setting is set to **Prompt for credentials**, malware imitating the credential prompt might be able to gather the credentials from the user. However, the malware doesn't gain elevated privilege and the system has other protections that mitigate malware from taking control of the user interface even with a harvested password. While malware could present an imitation of the secure desktop, this issue can't occur unless a user previously installed the malware on the PC. Because processes requiring an administrator access token can't silently install when UAC is enabled, the user must explicitly provide consent by selecting **Yes** or by providing administrator credentials. The specific behavior of the UAC elevation prompt is dependent upon security policies. @@ -109,34 +109,34 @@ To better understand each component, review the following tables: |Component|Description| |--- |--- | -|

User performs operation requiring privilege|

If the operation changes the file system or registry, Virtualization is called. All other operations call ShellExecute.| -|

ShellExecute|

ShellExecute calls CreateProcess. ShellExecute looks for the ERROR_ELEVATION_REQUIRED error from CreateProcess. If it receives the error, ShellExecute calls the Application Information service to attempt to perform the requested task with the elevated prompt.| -|

CreateProcess|

If the application requires elevation, CreateProcess rejects the call with ERROR_ELEVATION_REQUIRED.| +|User performs operation requiring privilege|If the operation changes the file system or registry, Virtualization is called. All other operations call ShellExecute.| +|ShellExecute|ShellExecute calls CreateProcess. ShellExecute looks for the ERROR_ELEVATION_REQUIRED error from CreateProcess. If it receives the error, ShellExecute calls the Application Information service to attempt to perform the requested task with the elevated prompt.| +|CreateProcess|If the application requires elevation, CreateProcess rejects the call with ERROR_ELEVATION_REQUIRED.| ### System |Component|Description| |--- |--- | -|

Application Information service|

A system service that helps start apps that require one or more elevated privileges or user rights to run, such as local administrative tasks, and apps that require higher integrity levels. The Application Information service helps start such apps by creating a new process for the application with an administrative user's full access token when elevation is required. Depending on the configured policies, the user may give consent.| -|

Elevating an ActiveX install|

If ActiveX isn't installed, the system checks the UAC slider level. If ActiveX is installed, the **User Account Control: Switch to the secure desktop when prompting for elevation** Group Policy setting is checked.| -|

Check UAC slider level|

UAC has a slider to select from four levels of notification.