Thanks for asking question! As its documented here Important update for Tinfoil security - Azure App Service,
"We’re announcing that Tinfoil Security addon will no longer be available through App Service."
As per my knowledge Azure does not provide any internal web vulnerability testing tools. Just like “Tinfoil Security”, you need to use a third-party application to do the vulnerability scan.
Here are some third-party reference documents:
a. For “Tinfoil Security”, you can visit the official website of "Tinfoil Security" for consulting, url: API Security Testing & DAST Tools | Tinfoil (tinfoilsecurity.com).
b. You can kindly read this document, OWASP Foundation | Open Source Foundation for Application Security, to find a third-party security tool.
c. In addition, refer to Vulnerability Scanning Tools | OWASP, this document lists many third-party web vulnerability scanning tools.
Hope this helps, let us know.
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