Security Considerations

ASP.NET Security Settings
ASP Security Settings
General Guidelines

ASP.NET Security Settings

FileUpEE's interceptor - the HttpModule - caches request data before it is processed by ASP.NET.

The HttpModule writes to the hard drive as the same account as the application under which it is running, and can write to any directory on the server. The HttpModule can cache to a network share, but only if the account has network privileges.

The location of the temporary directory can be configured in the web.config file. To set the HttpModule temp directory:

Open the web.config file for the web site.
Navigate to the FileUpEETempDir application key under the <appSettings> node.
In Value attribute, enter the path and folder name.

In ASP.NET, if impersonation is disabled - as it is by default - FileUpEE executes in the context of the NETWORK_SERVICE account (in IIS 6) or the ASPNET account (in IIS 5.1). To allow uploads, the NETWORK_SERVICE account or ASPNET account must have Read, Write, and Modify permissions for FileUpEE's temporary and destination folders. An upload's destination folder is set in code by DestinationDirectory, DestinationPath, or SaveAs.

In a 3 tier upload (client -> web server -> file server) FileUpEE will use two temporary folders, one on the Web server and one on the file server. Both temporary folders require Read, Write, and Modify permissions for the ASPNET or authenticated user account under which the application is running on that machine.

Under ASP.NET impersonation is controlled in the .NET configuration file for your web application - web.config or machine.config (For information about these files, see Installing FileUpEE for ASP.NET). If no userName or password is set, the application will run in the user set in IIS just as it would for an ASP application. To enable impersonation, set impersonate to true in the <identity> node in the <system.web> section of web.config or machine.config:

<identity impersonate="true" userName="" password=""/>

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ASP Security Settings

In ASP, FileUpEE executes in a specific user context:

IUSR_MACHINENAME (The default anonymous user account)

OR
An authenticated user account

To allow uploads, the IUSR_MACHINENAME or authenticated user must have Read, Write, and Modify NTFS permissions for FileUpEE's temporary and destination folders. An upload's destination folder is set in code by DestinationDirectory, DestinationPath, or SaveAs. The temporary directory for an upload can be set in code by the property TempStorageLocation. If you do not assign a value to TempStorageLocation, uploads will be cached in the system's default directory for cached files, which is determined by the system environment variable TEMP.

To change the system's default directory for cached files, reset the TEMP environment variable, as follows:

Open the Control Panel.
Select System.
Select the Advanced tab.
Click Environment variables...
Select TEMP from the System Variables list.
Click Edit.
Enter a new Variable Value, and click Ok.

In a 3 tier upload (client -> web server -> file server) FileUpEE will use two temporary folders -- one on the Web server and one on the file server. Both temporary folders require Read, Write, and Modify permissions for the anonymous or authenticated user.

If UseMemory is set to True, FileUpEE will not write temporary files and it is not necessary to set permissions for a temporary directory.

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General Guidelines

Don't allow write access to critical directories such as "C:\", "C:\WINNT", and "C:\WINNT\System32".
Do audit scripts to ensure that ASP developers are writing to correct locations.
Do audit scripts to ensure that an instance of FileUpEE is not created as an Application variable.
Do use the TempStorageLocation property to set an appropriate temporary directory. FileUpEE needs a file cache to function. If the TempStorageLocation property is not set, FileUpEE will use the default temporary directory of the system.
Don't prevent the IUSR_MACHINENAME account for ASP from reading the system registry, especially the HKEY_CLASSES_ROOT hive.
Don't prevent the IUSR_MACHINENAME account (for ASP) or the ASPNET or NETWORK_SERVICES accounts (for ASP.NET) from reading FileUpEE.DLL or MimeClient.dll.
Don't leave the default Everyone-Everything permission on a publicly available web server.

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