FindAdminAccess

A C# utility that enumerates domain computers and tests administrative access to them, including connectivity checks, admin privileges verification, and C$ share writability testing.

Features

• Enumerate all computers in an Active Directory domain
• Test network connectivity
• Verify administrative access using Service Control Manager (SCM) API
• Test C$ administrative share writability
• Support for both synchronous and asynchronous processing
• Flexible domain and domain controller specification
• Single computer testing mode

Requirements

• .NET Framework (or .NET Core/5+)
• Windows operating system
• Domain-joined machine or domain credentials
• Appropriate Active Directory query permissions
• Administrative rights on target computers (to verify access)

Usage

Basic Syntax

FindAdminAccess.exe [options]

Options

Examples

Test all computers in the current domain (synchronous):

FindAdminAccess.exe

Test all computers asynchronously (faster but resources heavy):

FindAdminAccess.exe --async

Specify domain and domain controller:

FindAdminAccess.exe --domain contoso.com --dc dc01.contoso.com

Test a specific computer:

FindAdminAccess.exe --computer SERVER01 --async

Output

The tool displays results in a table format:

Computer Name                  Online          Admin Handle    C$ Writable
---------------------------------------------------------------------------
SERVER01.contoso.com           Yes             Yes             Yes
WORKSTATION02.contoso.com      Yes             No              N/A
OFFLINE-PC.contoso.com         No              N/A             N/A

Column Descriptions

• Computer Name: FQDN of the computer
• Online: Whether the computer responds to ping
• Admin Handle: Whether administrative access (SCM) is available
• C$ Writable: Whether the administrative C$ share is writable

How It Works

1. Computer Enumeration: Queries Active Directory using PrincipalContext and ComputerPrincipal to retrieve all computer objects
2. Connectivity Check: Uses ICMP ping with 1-second timeout to verify network connectivity
3. Admin Access Test: Attempts to open Service Control Manager with SC_MANAGER_ALL_ACCESS rights via P/Invoke
4. C$ Share Test: Tries to create and delete a test file on the administrative C$ share

Building

Visual Studio

1. Open the solution in Visual Studio
2. Build the project (Ctrl+Shift+B)

Command Line

csc /out:FindAdminAccess.exe Program.cs

Or with .NET CLI:

dotnet build

Troubleshooting

If you encounter domain connection errors, try these steps:

1. Verify DNS resolution of the domain/DC
2. Check if LDAP ports (389/636/3268/3269) are accessible
3. Try using just --dc without --domain parameter
4. Try using the DC's FQDN instead of IP address
5. Ensure you have domain query permissions

Notes

• Local machine testing is in the TODO
• Async mode significantly increases performance for large domains
• Failed admin access attempts do not generate verbose errors by default (can be enabled in code)

Author

Lsecqt