hunt-html-injection SKILL.md skillB
hunt-html-injection 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-html-injection@git:20260910.546fe86Pins git:20260910.546fe86 in mdr.lock. Pin the fingerprint instead.
- Audit grade
- B, 16 of 17 checks passed
- Kind
- SKILL.md skill
- Repository
- novaestellar/novahaku
- Path
testing/hunt/hunt-html-injection/SKILL.md- Versions recorded
- 3
- Latest version
- git:20260910.546fe86, committed Sep 10, 2026
- First version recorded
- Sep 3, 2026
- Size
- 3,453 bytes
- Repository stars
- 28
- License
- MIT
Hunt HTML Injection — user-supplied input is rendered as raw HTML in the response without sanitisation, allowing an attacker to inject arbitrary HTML tags (but not necessarily JavaScript). Lower severity than XSS but enables phishing, UI manipulation, and credential harvesting via injected forms. Use when testing text-display surfaces (search results, profile fields, comments, error messages, feedback forms). For markup that executes JavaScript, escalate to hunt-xss.
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
## What is HTML Injection HTML Injection occurs when user input is inserted into a page's HTML without escaping, so injected tags are rendered by the browser as markup rather than displayed as literal text. Unlike XSS, the injected content does not require JavaScript execution — injecting `<b>`, `<h1>`, `<a>`, `<img>`, or `<form>` tags is sufficient. **To PROVE impact unambiguously, escalate to an active vector carrying a unique numeric canary** — e.g. `"><img src=x onerror=alert(91234)>` or `<svg onload=alert(91234)>`. A distinctive 4+ digit number (not `alert(1)`) distinguishes YOUR reflected injection from the example payloads practice pages embed in their own hint text. Proof = the raw, unescaped vector with your canary appears in the response. **Impact:** - Phishing via injected `<form>` or `<a href="attacker.com">` tags - UI defacement — `<h1>HACKED</h1>` renders visually on the page - Credential harvesting via injected login forms - Redirect via `<meta http-equiv="refresh">` - Stepping stone to XSS (may be blocked by WAF on `<script>` but not `<img onerror>`) ## Attack Surface Any input that is reflected or stored and then displayed in an HTML context: …
Read the whole file at its exact version.
How to install
mdr add novaestellar/novahaku/hunt-html-injection@sha256:f860af543afefb44The 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_maz6xswh63uz7yhe)
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 | 3,453 B | B | view · diff |
| git:20260903.29924dd | 2026-09-03 | 29924dd | 3,465 B | B | view · diff |
| git:20260903.fa855c4 | 2026-09-03 | fa855c4 | 3,436 B | B | view |
Audit of the latest version
- 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 (3453 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
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_maz6xswh63uz7yhe GET https://markdownregistry.com/api/v1/resolve?ref=novaestellar/novahaku/hunt-html-injection GET https://markdownregistry.com/api/v1/blob/f860af543afefb4406abf2f60b7420fb7be06ce846a2ddf927ffafd76d6716b9
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.