cors-cross-origin-misconfiguration

Detect CORS misconfigurations in web applications by analyzing HTTP headers.

Updated Jun 11, 2026
One-click install
npx skills add https://github.com/utsavthakur/agenticskills --skill cors-cross-origin-misconfiguration-utsavthakur
Or copy as Structured Prompt for Agent
Please help me install this Agent Skill.
Skill: cors-cross-origin-misconfiguration
Source: https://github.com/utsavthakur/agenticskills/tree/main/cors-cross-origin-misconfiguration
Command: npx skills add https://github.com/utsavthakur/agenticskills --skill cors-cross-origin-misconfiguration-utsavthakur

SYSTEM DOCUMENTATION & REQUIREMENTS

💡 This Skill requires requests, beautifulsoup4, html.parser, and includes scripts (resource) and references (resource) components.

What problem does it solve?

This Skill helps identify and analyze Cross-Origin Resource Sharing (CORS) misconfigurations, which can lead to security vulnerabilities in web applications.

Core Features & Use Cases

  • CORS Misconfiguration Detection: Identifies and reports common CORS misconfigurations such as wildcard with credentials, reflected origin, weak allowlist, and null origin.
  • Detailed Analysis: Provides deep insights into the implications of each misconfiguration and suggests remediation steps.
  • Use Case: Use this Skill to scan a web application for CORS misconfigurations and understand the potential risks to user data and system integrity.

Quick Start

Load the cors-cross-origin-misconfiguration skill to scan your web application for CORS misconfigurations.

Frequently Asked Questions about cors-cross-origin-misconfiguration

High-intent search queries and answers about installing and using this skill.

FAQPage Schema
How do I detect CORS misconfigurations in a web application?

You can detect CORS misconfigurations by scanning HTTP headers and access control policies to identify issues like wildcard origins with credentials, origin reflection, or null origin trust. This analysis reveals potential credential leakage and trust boundary errors.

What are common CORS vulnerabilities like origin reflection and null origin?

Common CORS vulnerabilities include wildcard origins combined with credentials, reflected origins bypassing allowlists, and null origin trust. These misconfigurations expose web applications to credential leakage and unauthorized cross-origin data access.

Can I use Python and BeautifulSoup to analyze cross-origin resource sharing policies?

Yes, this approach uses Python with the requests and beautifulsoup4 libraries to parse HTTP headers and analyze cross-origin resource sharing policies. It processes HTTP responses to identify weak allowlists and trust boundary errors.

What is the best way to scan for wildcard and reflected origin CORS issues?

The best way to scan for wildcard and reflected origin CORS issues is to analyze HTTP access control headers systematically. This process identifies reflected origins, weak allowlists, and null origin trusts while providing remediation steps for each detected vulnerability.

Why does my CORS configuration allow credential leakage from reflected origins?

CORS configurations allow credential leakage when servers reflect arbitrary origins while permitting credentials. This misconfiguration occurs due to weak allowlist validation or trust boundary errors in HTTP access control policy headers.

Do I need to install requests and beautifulsoup4 to check for CORS trust boundary errors?

Yes, you need the requests and beautifulsoup4 Python libraries installed to parse HTTP headers and analyze access control policies. These dependencies are required to identify trust boundary errors and credential leakage vulnerabilities.