[Bug] NullReferenceException in UserProfilePicTransform.cs when PortalSettings is null

[thienvc]

Description I encountered a potential NullReferenceException in the UserProfilePicTransform class while debugging the DNN Platform source code.

Specifically, in the method that handles the image transformation, PortalController.Instance.GetCurrentSettings() is called to retrieve the current portal settings. Immediately after, the code attempts to access settings.PortalId.

If GetCurrentSettings() returns null (which can happen if the Image Handler is requested in a context where the Portal Settings are not correctly resolved, e.g., missing alias or direct handler request), the application throws an exception.

Location

File: DNN Platform/Library/Services/GeneratedImage/StartTransform/UserProfilePicTransform.cs

Lines: ~78-79 (depending on the version)

https://github.com/dnnsoftware/Dnn.Platform/blob/8ceb145f4e478552a20484d0cb2b607d16ca5d97/DNN%20Platform/Library/Services/GeneratedImage/StartTransform/UserProfilePicTransform.cs#L78C13-L79

var settings = PortalController.Instance.GetCurrentSettings(); var targetUser = UserController.Instance.GetUser(settings.PortalId, this.UserID);

Steps to Reproduce

Debug the UserProfilePicTransform.cs file.

Trigger an image transformation request in a scenario where the HttpContext or PortalAlias is not fully resolved (causing GetCurrentSettings() to return null).
login as host user, and browser request url
https://dnndev.me/DnnImageHandler.ashx?mode=profilepic&userId=1&h=32&w=32&cdv=639040729629470000

Observe the crash at settings.PortalId.

Expected Behavior The code should perform a null check on settings before accessing its properties. If settings is null, the transformation should gracefully abort or use a fallback mechanism instead of throwing an unhandled exception.

[thienvc]

It turns out that my AUM_IgnoreUrlRegex setting with DnnImageHandler.ashx($|?) caused HttpModule to ignore the PortalSettings.
I'm not sure when I added it.