hunt-cors SKILL.md skillF
hunt-cors from novaestellar/novahaku is an agent skill: a SKILL.md folder an AI agent loads when a task calls for it.
mdr add novaestellar/novahaku/hunt-cors@git:20260910.546fe86Pins git:20260910.546fe86 in mdr.lock. Pin the fingerprint instead.
- Audit grade
- F, 15 of 17 checks passed
- Kind
- SKILL.md skill
- Repository
- novaestellar/novahaku
- Path
testing/hunt/hunt-cors/SKILL.md- Versions recorded
- 3
- Latest version
- git:20260910.546fe86, committed Sep 10, 2026
- First version recorded
- Sep 3, 2026
- Size
- 14,063 bytes
- Repository stars
- 28
- License
- MIT
Hunt CORS Misconfiguration — origin-reflection with credentials, null-origin trust, subdomain-regex bypass (unanchored vs unescaped-dot vs prefix-only), pre-flight (OPTIONS) gating bypass, postMessage origin checks. High only when an attacker-controlled origin can perform a CREDENTIALED cross-origin read of sensitive data and you have proven it in a browser. Use when testing API endpoints, SPAs, or any app emitting Access-Control-* headers.
Collected from public GitHub. Every version is saved exactly as it was and never changes. Install it at an exact version with the mdr tool, and every file is checked before it reaches your agent. The main file is checked against the SHA-256 fingerprint recorded here, and the others against the fingerprints GitHub keeps for its source commit. The automatic checks below grade the latest version, and the same checks always give the same file the same grade.
What the file says
# HUNT-CORS — Cross-Origin Resource Sharing Misconfiguration ## What actually pays (and what does not) CORS pays High **only** when an attacker-controlled origin can perform a **credentialed** cross-origin read of sensitive authenticated data, and you have a browser PoC proving the response body is readable from `evil.com`. Two hard browser rules that kill most "findings" — check these FIRST: - **`Access-Control-Allow-Origin: *` CANNOT be combined with credentials.** If the server returns `ACAO: *`, the browser refuses to send/expose the response for a `credentials: include` request. A wildcard-only endpoint is **not** credential-exploitable. It is only interesting if the data it serves is sensitive *without* a session (rare) — usually this is Informational/Low. - **`Access-Control-Allow-Credentials: true` is meaningless on its own.** It matters only if `ACAO` reflects/allows your specific attacker origin AND a cross-origin credentialed `fetch` actually returns a readable body. ACAC on a response that does not reflect your origin proves nothing. If you cannot demonstrate a readable cross-origin authed body in a real …
Read the whole file at its exact version.
How to install
mdr add novaestellar/novahaku/hunt-cors@sha256:4e8cd6fc600c12c4The line at the top of this page pins the label git:20260910.546fe86, which is what most people want. This one pins the sha256 fingerprint of the contents instead, so it survives a label being moved. Either way the exact version is written to mdr.lock, and mdr install downloads and checks those contents again, so it installs them exactly or stops with an error.
[](https://markdownregistry.com/a/art_3m4uzi6sfyzbtqjh)
6 badge image fetches in 30 days. What the badge shows.
Versions
The registry has recorded 3 versions of this file, between Sep 3, 2026 and Sep 10, 2026, about one every 3 days.
| version | committed | commit | size | audit | |
|---|---|---|---|---|---|
| git:20260910.546fe86 latest | 2026-09-10 | 546fe86 | 14,063 B | F | view · diff |
| git:20260903.29924dd | 2026-09-03 | 29924dd | 14,075 B | F | view · diff |
| git:20260903.fa855c4 | 2026-09-03 | fa855c4 | 14,046 B | F | view |
Audit of the latest version
- FAIL, critical: No link to an exfiltration or paste host (matched: https://OOB-ID.oastify.com)
- fail: No script tag (matched: <script)
- pass: Frontmatter block present
- pass: Frontmatter declares a name
- pass: Frontmatter declares a description
- pass: Size between 200 bytes and 200 KB (14063 bytes)
- pass: No zero-width or bidi control characters
- pass: No instruction hidden inside an HTML comment
- pass: No credential-shaped string
- pass: No instruction to send local credentials anywhere
- pass: No text hidden with inline styles
- pass: No prompt-injection phrasing
- pass: No curl or wget piped into a shell
- pass: No recursive delete of root, home or parent
- pass: No instruction to read or print local credentials
- pass: No base64 blob over 200 characters
- pass: No link to a raw IP address
Starting a new one? Use a template for SKILL.md on mdpantry, which passes every one of these checks and says what to change in it.
Source
novaestellar/novahaku · 28 stars · license MIT · pushed 2026-09-28 · branch main
API
GET https://markdownregistry.com/api/v1/artifacts/art_3m4uzi6sfyzbtqjh GET https://markdownregistry.com/api/v1/resolve?ref=novaestellar/novahaku/hunt-cors GET https://markdownregistry.com/api/v1/blob/4e8cd6fc600c12c45b5f48db11a414eff17f638c9441a5b040ed63d0e25d0465
Your AI assistant does the legwork. You hear about the deals worth your word. Hand yours the standing instructions at modelranch.com and it joins the network that reads files like this one.
Guides: the SKILL.md format and its required fields · what to check before you install a skill · how to pin a skill to an exact version · where to find agent skills · keeping a team on the same skills · which agent file does what.