Cors Review

Q: What is a Claude Code skill and how does the Cors Review skill fit in?

A Claude Code skill is a SKILL.md file that lives under ~/.claude/skills/<name>/ and tells the Claude Code CLI agent how to perform a specific task (instructions, prompts, allowed tools). Skills are auto-discovered at session start. Cors Review is one of 67,000+ skills indexed in the open ClaudSkills catalog, classified under the Security category. Learn more at https://claudskills.com/learn/what-is-skill-md/.

Category: Security · Sub-category: web-security · Last updated: 2026-10-25

type:scanner type:review

Review a web application's Cross-Origin Resource Sharing configuration (allowed origins, credentials, methods, headers, preflight caching, exposed headers) against a checklist of the mistakes that leak data cross-site or break legitimate clients, and produce the correct configuration for the framework or gateway in use. Use when a browser says \"blocked by CORS policy\", when an API must be called from another origin, or when a scanner flags a permissive policy. Not for CSRF defence in general (CORS is not a CSRF mechanism; the checklist says what is) and not for CSP.

Security AStatic scan found no risk patternsHow grading works ›

From the source SKILL.md

CORS errors get fixed in a hurry with `, and ` with credentials is a data leak to every site on the internet. This skill reviews what the server sends, what the clients need, and the gap between them, using the checklist in [references/checklist.md](references/checklist.md), and produces a configuration that allows exactly the origins that need access.

What this skill does

Cors Review is a community-contributed Claude Code skill in the web-security sub-category. It ships as a SKILL.md file that Claude Code auto-discovers under ~/.claude/skills/cors-review/ and loads when your prompt matches the skill's trigger.

When to invoke it: Use when a browser says \"blocked by CORS policy\", when an API must be called from another origin, or when a scanner flags a permissive policy. Not for CSRF defence in general (CORS is not a CSRF mechanism; the checklist says what is) and not for CSP.

Who uses this skill

The Cors Review Claude Code skill is built for security engineers, penetration testers, DevSecOps practitioners, and development teams hardening codebases and infrastructure. It's part of ClaudSkills (also referred to as Claude Skills or Claude Code Skills) — the open community-curated registry of 211,000+ SKILL.md files for Anthropic's Claude Code agent and the wider Claude ecosystem (Claude API, Claude Agent SDK).

How to install

Free

Manual install (2 steps)

mkdir -p ~/.claude/skills/cors-review
curl -L https://claudskills.com/skills/cors-review/SKILL.md \
  -o ~/.claude/skills/cors-review/SKILL.md

Or just download SKILL.md directly and drop it into ~/.claude/skills/cors-review/. Claude Code auto-discovers it on next session.

Skills live at ~/.claude/skills/cors-review/SKILL.md on macOS/Linux, or %USERPROFILE%\.claude\skills\cors-review\SKILL.md on Windows. See the full install guide for step-by-step instructions.

📱 Install from your phone or desktop Telegram

Open @claudskills_bot on Telegram, tap Open Desktop App, and the desktop app installs this skill for you. Or share the bot link with a colleague — they get the same one-tap install. Learn more →

Pro

One-click install via the desktop app

The ClaudSkills desktop app installs any skill directly into ~/.claude/skills/ with one click — no terminal required. Pro starts at $9/mo or $149 lifetime.

Pro

For the full experience including quality scoring and one-click install features for each skill — upgrade to Pro.

See pricing → Download desktop app

Frequently asked questions

How do I install the Cors Review Claude Code skill?

Install via the ClaudSkills desktop app (one click) or copy SKILL.md from the source repository to ~/.claude/skills/cors-review/SKILL.md and restart Claude Code. Both flows are detailed at claudskills.com/install/.

What does the Cors Review skill do?

Is this skill free to install?

Yes. ClaudSkills is an open registry — every skill keeps its source repository's license, and manual install via copy is free. ClaudSkills Pro ($9/mo, $79/yr, or $149 one-time) adds one-click install via the desktop app and a multi-signal Quality Score.

When should I use the Cors Review skill?

Use Cors Review when your Claude Code task falls under the Security category — specifically in the web security area. Claude Code auto-discovers installed skills and invokes the right one based on the task description, so you can also ask Claude directly (e.g. "use Cors Review" or describe the task and let Claude pick). Browse related skills at /category/security/.

What is a Claude Code skill and how does the Cors Review skill fit in?

A Claude Code skill is a SKILL.md file that lives under ~/.claude/skills/<name>/ and tells the Claude Code CLI agent how to perform a specific task (instructions, prompts, allowed tools). Skills are auto-discovered at session start. Cors Review is one of 67,000+ skills indexed in the open ClaudSkills catalog, classified under the Security category. Learn more at /learn/what-is-a-claude-skill/.

Attribution & license

Source: https://github.com/basitalisandhu/claude-skills/blob/HEAD/plugins/security-basics/skills/cors-review/SKILL.md
License: MIT
Author: basitalisandhu
Website: https://basitalisandhu.github.io/claude-skills/

Cite this skill

If you reference this skill in a blog post, paper, or documentation, you can cite it as:

APA

basitalisandhu. (2026). Cors Review [Claude Code skill]. ClaudSkills. https://claudskills.com/skills/cors-review/

BibTeX

@misc{cors-review-2026,
  author    = {basitalisandhu},
  title     = {Cors Review [Claude Code skill]},
  year      = {2026},
  publisher = {ClaudSkills},
  url       = {https://claudskills.com/skills/cors-review/}
}

Embed this skill

Promote, attribute, or link this skill from your own README, blog post, or documentation. All three snippets are free to use — no sign-up, no API key. More distribution surfaces →

Badge

[![ClaudSkills](https://claudskills.com/badge/cors-review.svg)](https://claudskills.com/skills/cors-review/?utm_source=badge&utm_medium=readme&utm_campaign=skill_badge)

Security scan

Grade A · scanned 2026-10-25 — free static scan against the OWASP Agentic Skills Top 10.

No risk patterns were found in any of the ten OWASP-aligned categories. How grading works ›

✓ Prompt injection
✓ Data exfiltration
✓ Supply chain
✓ Reverse shell
✓ Credentials
✓ Execution
✓ Filesystem
✓ Persistence
✓ Obfuscation
✓ Network

Show this grade on your repo (click to copy):

[![Security: A](https://img.shields.io/badge/Security-A-2e7d32)](https://claudskills.com/skills/cors-review/#security)

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Browse all Security skills in the ClaudSkills registry, or explore these other picks from the same category:

Browse all Security skills → Top 100 skills

Part of ClaudSkills — the open registry for Claude Skills & Claude Code Skills. · What's New · Install guide · About · llms.txt

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