Preface: Due to the need for high-security, compliance (HIPAA, GDPR), and transaction reliability, many banks and financial firms use ASP[.]NET. The primary difference is that ASP[.]NET (often called “ASP[.]NET Framework”) is the original, Windows-only version, while ASP[.]NET Core is a modern, cross-platform includes Windows, macOS, and Linux.

Background: The Microsoft 365 ecosystem relies heavily on ASP[.]NET Core for its modern, high-traffic web components:

Microsoft Teams: The backend for Teams is built on ASP[.]NET Core to handle the massive, real-time demands of millions of concurrent users.

Office Web Apps: Core parts of the web-based versions of Word, Excel, and Outlook utilize the[.]NET architecture for cross-platform stability.

 Bing & SharePoint: These services are frequently cited as being “proven at hyperscale” using the ASP[.]NET Core framework.

ASP[.]NET Core’s Kestrel server can handle over 7 million requests per second.

Ref: When you use an official Microsoft [.]NET Docker image, Kestrel is already there. When your container starts, it runs dotnet Myapp[.]dll, which immediately fires up Kestrel to listen for requests.

# Kestrel (Inside Container) → Receives the “cleaned” request from the proxy and runs your ASP[.]NET Core logic.

In Kubernetes, your “Pod” runs that Docker container. Kestrel handles the traffic inside that Pod. 

Vulnerability details: Improper verification of cryptographic signature in ASP[.]NET Core allows an unauthorized attacker to elevate privileges over a network.

Official announcement: Please refer to the link for details – https://nvd.nist.gov/vuln/detail/CVE-2026-40372