validating-cors-policies
Validate CORS policies for security issues and misconfigurations.
Skill by bostannnn
Install
Works with Claude Code. Read the repository before you give any tool access to your data.
npx agentmarket install skill/bostannnn-validating-cors-policies
Asks which of your tools to add it to (Claude Code, Codex, Cursor, VS Code, Windsurf, Gemini CLI, Claude Desktop) and shows the change first. See https://agentmart.dev/cli.
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About
Use cases: security
Reviews
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Permissions
What this skill can do and what it asks for, from its SKILL.md. Checked Oct 25, 2026.
- Tools
- No tools found
- Secrets
- None asked for
- Install scripts
- None found
- Runs as
- Python package
Network hosts it talks to 1
codeload.github.com· found in install command
Files it touches
~/.claude/skills/validating-cors-policies
Tools it pre-approves 4
From allowed-tools in SKILL.md: the agent may use these without asking you each time.
Read,WebFetch,WebSearch,Grep
What's inside
- Skill name
validating-cors-policies- Description
- Validate CORS policies for security issues and misconfigurations. Use when reviewing cross-origin resource sharing. Trigger with 'validate CORS', 'check CORS policy', or 'review cross-origin'.
- License
- MIT
- Allowed tools
- Read,, WebFetch,, WebSearch,, Grep
- Instructions
- 91 lines in SKILL.md · view on GitHub
Before installing
- Ships executable scripts
Files (6)
- SKILL.md
- README.md · assets/
- README.md · references/
- README.md · scripts/
- generate_test_cases.py · scripts/
- validate_cors.py · scripts/
SKILL.md (first lines)
# Cors Policy Validator
This skill provides automated assistance for cors policy validator tasks.
## Overview
This skill empowers Claude to assess the security and correctness of CORS policies. By leveraging the cors-policy-validator plugin, it identifies misconfigurations and potential vulnerabilities in CORS settings, helping developers build more secure web applications.
## How It Works
1. **Analyze CORS Configuration**: The skill receives the CORS configuration details, such as headers or policy files.
2. **Validate Policy**: It utilizes the cors-policy-validator plugin to analyze the provided configuration against established security best practices.
3. **Report Findings**: The skill presents a detailed report outlining any identified vulnerabilities or misconfigurations in the CORS policy.
## When to Use This Skill
This skill activates when you need to:
- Validate a CORS policy for a web application.
- Check the CORS configuration of an API endpoint.
- Identify potential security vulnerabilities in existing CORS implementations.
## Examples
### Example 1: Validating a CORS Policy File
User request: "Validate the CORS policy in `cors_policy.json`"
The skill will:
1. Read the `cors_policy.json` file.
2. Use the cors-policy-validator plugin to analyze the CORS configuration.
3. Output a report detailing any identified vulnerabilities or misconfigurations.
### Example 2: Checking CORS Headers for an API Endpoint
User request: "Check CORS headers for the API endpoint at `https://example.com/api`"
The skill will:
1. Fetch the CORS headers from the specified API endpoint.
2. Use the cors-policy-validator plugin to analyze the headers.
3. Output a report summarizing the CORS configuration and any potential issues.
## Best Practices
- **Configuration Source**: Always specify the source of the CORS configuration (e.g., file path, URL) for accurate validation.
- **Regular Validation**: Regularly validate CORS policies, especially after making changes to the application or API.
- **Heuristic Analysis**: Consider supplementing validation with manual review and heuristic analysis to catch subtle vulnerabilities.
## Integration
This skill can be integrated with other security-related plugins to provide a more comprehensive security assessment. For example, it can be used in conjunction with vulnerability scanning tools to identify potential cross-site scripting (XSS) vulnerabilities related to CORS misconfigurations.
## Prerequisites
- Access to codebase and configuration files in {baseDir}/
- Security scanning tools installed as needed
- Understanding of security standards and best practices
- Permissions for security analysis operations
## Instructions
1. Identify security scan scope and targets
2. Configure scanning parameters and thresholds
3. Execute security analysis systematically
4. Analyze findings for vulnerabilities and compliance gaps
5. Prioritize issues by severity and impact
6. Generate detailed security report with remediation steps
## Output
- Security scan results with vulnerability details
- Compliance status reports by standard
- Prioritized list of security issues by severity
- Remediation recommendations with code examples
- Executive summary for stakeholders
## Error Handling
If security scanning fails:
- Verify tool installation and configuration
- Check file and directory permissions
- Validate scan target paths
- Review tool-specific error messages
- Ensure network access for dependency checks
## Resources
- Security standard documentation (OWASP, CWE, CVE)
- Compliance framework guidelines (GDPR, HIPAA, PCI-DSS)
- Security scanning tool documentation
- Vulnerability remediation best practicesFrom bostannnn/Sere, MIT.
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Signals
- Stars
- 0
- Forks
- 0
- Open issues
- 0
- Last commit (this folder)
- Mar 2, 2026 (8 months ago)
From GitHub (fetched Oct 24, 2026).
Details
- License
- MIT
- Repository
- github.com/bostannnn/Sere
- First seen
- Oct 24, 2026
- Last checked
- Oct 24, 2026
- Source
- GitHubgithub-graphql
More from bostannnn
- 0.414score
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Use this skill immediately when the user mentions merge conflicts that need to be resolved.
SkillDFreshness: DClaude Code +9 - 0.405score
typescript-review
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Review TypeScript and JavaScript code changes for compliance with Metabase coding standards, style violations, and code quality issues.
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Cite this page
validating-cors-policies skill. Agent Mart. https://agentmart.dev/skills/bostannnn-validating-cors-policies (last updated 2026-10-24)