What are the most common IIS security risks?

Common IIS security risks include misconfigurations such as directory listing, exposed WebDAV functionality, weak SSL/TLS settings, and improper authentication controls. Application-layer vulnerabilities such as SQL injection and XSS are also common in IIS-hosted web applications.

How do I secure an IIS server?

To secure an IIS server, you should reduce server exposure, apply least-privilege NTFS permissions, configure request filtering, disable unnecessary features like WebDAV and FTP, enforce modern TLS, and continuously validate security using automated scanning.

What is IIS hardening?

IIS hardening is the process of securing an IIS web server by applying configuration best practices, restricting access, disabling unnecessary functionality, and aligning the system with a defined security baseline.

Does IIS security include application security?

Yes. IIS security includes both server configuration and the security of the web applications running on the server. Even a well-configured IIS server can host vulnerable applications, so continuous testing with a DAST solution is essential to identify and validate application-layer vulnerabilities in IIS-hosted web applications as they evolve over time.

Author Archives Zbigniew Banach

THE AUTHOR

Zbigniew Banach
Technical Content Lead & Managing Editor

Cybersecurity writer and blog managing editor at Invicti Security. Drawing on years of experience with security, software development, content creation, journalism, and technical translation, he does his best to bring web application security and cybersecurity in general to a wider audience.

IIS security best practices: How to secure an IIS server and web applications

Web Security Zone | May 27, 2026 by Zbigniew Banach

Learn how to secure Microsoft IIS with practical hardening best practices, attacker-focused insights, and continuous validation strategies. This guide covers common IIS misconfigurations, real-world exploitation techniques, and how to protect web applications running on IIS servers.

SNI proxy SSRF vulnerabilities: Misconfigurations, exploitation, and defense

Web Security Zone | May 26, 2026 by Zbigniew Banach

SNI proxy SSRF is a lesser-known but high-impact vulnerability class where misconfigured proxies route traffic based on attacker-controlled TLS metadata. Under specific conditions, this can expose internal services and even cloud metadata endpoints in AWS and Azure. This article explains how these attacks work, when they are exploitable, and how to defend against them.

What is an IDOR vulnerability?

Web Security Zone | May 22, 2026 by Zbigniew Banach

Insecure direct object references (IDOR) are a type of access control vulnerability where an application exposes internal object identifiers – such as user IDs, order numbers, or file names – without verifying whether the requesting user is authorized to access them. IDOR is no longer…

Your session cookies are probably misconfigured: How to fix cookie security flags

Web Security Zone | May 21, 2026 by Zbigniew Banach

Understand how to correctly implement cookie security flags in modern web applications. Includes practical examples, browser behavior nuances, and guidance on HttpOnly, Secure, and SameSite settings.

Top 10 dynamic application security testing (DAST) tools for 2025

Web Security Zone | March 20, 2025 by Zbigniew Banach

This guide explores the top 10 DAST tools for 2025, highlighting the best commercial solutions as well as open-source options. Learn how the right tools can help you build DAST-first AppSec to secure your applications in production, integrate with DevSecOps, and minimize your web application security risk.

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