Top 20 NuGet anti Packages

Cleans HTML from constructs that can be used for cross site scripting (XSS)
Rule based HTML sanitizer using a white list. Documentation at: https://github.com/Vereyon/HtmlRuleSanitizer
ProceXSS is a Asp.NET Http module for preventing xss attacks.
You can do a lot of http requests through different proxies.
A package to secure all controllers actions in your application by default by disallowing anonymous access, and requiring each HttpPost action to be passed an anti-forgery token. Anonymous access to a controller action needs to be explicitly set by use of an attribute.