novaestellar/novahaku · testing/hunt/hunt-host-header/SKILL.md

hunt-host-header skillA

hunt-host-header is agent-read markdown (skill) from novaestellar/novahaku: Hunt Host Header Injection — password reset poisoning → ATO, web cache poisoning via unkeyed Host/X-Forwarded-Host, routing-based SSRF (Host picks upstream → cloud metadata/internal services), path-override SSRF/ACL-bypass (X-Original-URL/X-Rewrite-URL), OAuth redirect_uri/issuer poisoning, and absolute-URL link poisoning in emails. High to Critical when it reaches ATO or mass cache poisoning. Built on public Host-header research (PortSwigger 'Practical web cache poisoning' + James Kettle, and t.

Indexed from public GitHub and served as immutable, content-addressed versions. Install it pinned to an exact SHA-256 with the mdr CLI, and every file is verified against the hash recorded here before it reaches your agent. The deterministic audit below grades the latest version, and the same file always earns the same grade.

How to install

Latest version
mdr add novaestellar/novahaku/hunt-host-header@git:20260910.546fe86
Exact content
mdr add novaestellar/novahaku/hunt-host-header@sha256:64ae269807ac41fd

Pin to a label to follow the author's releases, or to a sha256 to freeze the exact bytes forever. Either way the resolved hash is written to mdr.lock, and mdr install reproduces it on any machine.

Badge

mdr badge

[![mdr](https://markdownregistry.com/badge/art_mtzt7nbuyou3v25o.svg)](https://markdownregistry.com/a/art_mtzt7nbuyou3v25o)

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Versions

versioncommittedcommitsizeaudit
git:20260910.546fe86 latest2026-09-10 546fe86 14,118 BA view · diff
git:20260903.29924dd2026-09-03 29924dd 14,130 BA view · diff
git:20260903.fa855c42026-09-03 fa855c4 14,101 BA view

Audit of the latest version

A  17 of 17 checks passed. Deterministic, no model, same answer every run.
  • pass: Frontmatter block present
  • pass: Frontmatter declares a name
  • pass: Frontmatter declares a description
  • pass: Size between 200 bytes and 200 KB (14118 bytes)
  • pass: No zero-width or bidi control characters
  • pass: No instruction hidden inside an HTML comment
  • pass: No link to an exfiltration or paste host
  • 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
  • pass: No script tag

Source

GitHub

novaestellar/novahaku · 19 stars · license none · pushed 2026-09-10 · branch main

API

GET https://markdownregistry.com/api/v1/artifacts/art_mtzt7nbuyou3v25o
GET https://markdownregistry.com/api/v1/resolve?ref=novaestellar/novahaku/hunt-host-header
GET https://markdownregistry.com/api/v1/blob/64ae269807ac41fdef82679f080700f4d57f4b93bd1d29f43a601ec5febaa9de