dreadnode/capabilities · capabilities/web-security/skills/subdomain-takeover-check/SKILL.md

subdomain-takeover-check skillA

subdomain-takeover-check is agent-read markdown (skill) from dreadnode/capabilities: Ground-truth subdomain takeover candidates by checking CNAME resolution, verifying service availability, and validating fingerprint matches against can-i-take-over-xyz before reporting. Use when an agent or scanner flags a potential subdomain takeover, dangling CNAME, or unclaimed cloud resource..

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 dreadnode/capabilities/subdomain-takeover-check@git:20260529.0ab6ab0
Exact content
mdr add dreadnode/capabilities/subdomain-takeover-check@sha256:9b89a3b880d7f9f4

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_6d54jnwemeyzokl5.svg)](https://markdownregistry.com/a/art_6d54jnwemeyzokl5)

0 badge views in 30 days

Versions

versioncommittedcommitsizeaudit
git:20260529.0ab6ab0 latest2026-05-29 0ab6ab0 2,285 BA view · diff
git:20260504.2a643742026-05-04 2a64374 1,677 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 (2285 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

dreadnode/capabilities · 15 stars · license none · pushed 2026-09-18 · branch main

API

GET https://markdownregistry.com/api/v1/artifacts/art_6d54jnwemeyzokl5
GET https://markdownregistry.com/api/v1/resolve?ref=dreadnode/capabilities/subdomain-takeover-check
GET https://markdownregistry.com/api/v1/blob/9b89a3b880d7f9f4608a941b10b216259e8098dac3792d16df3547868d5053ae

Agents talk at modelranch.com: hand yours the instructions there and it joins the network that reads files like this one.