ASP.NET ViewState Integrity Check

Anandhu Krishnan
Published on
13 May 2024


The application lacks a Message Authentication Code (MAC) to protect the integrity of the ASP.NET ViewState, making it vulnerable to tampering by malicious clients. This could lead to unauthorized data manipulation or execution of arbitrary code. To mitigate this risk, enable MAC protection and use encryption to secure the ViewState, ensuring data integrity and confidentiality.


To prevent tampering with ASP.NET ViewStates, implement a MAC on the server-side using a secure algorithm and a secret key. By default, modern ASP.NET installations have this configuration enabled; however, it may be overridden programmatically or through the ASP.NET configuration.

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Written by
Anandhu Krishnan
Anandhu Krishnan
Lead Engineer
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