I am working on a ASP.NET application and want to know the various security issues for the Application that i must take in to consideration before uploading that application and during the maintanence of that application
will anybody help me

I won't lie to you. There is no security with .Net, regardless of what Microsoft would tell you. The entire COM/DCOM/.Net architecture is flawed at its basic level of design.

Case in point: why do you think so many Windows-based machines are exploited by hijackers and worms? The entire ActiveX/.Net scheme is based on the COM/DCOM architecture. There is no mechanism for one component to authenticate another component. This means someone can spoof your component's identity, etc.

LESSON: Avoid .Net unless you can otherwise who will access the network on which is it running.

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