hunt-xss

hunt-xss is a skill for Claude Code from Encod3d-Sec/TORCH. It costs 45 tokens per session (1,701 once invoked), scanned A, original, MIT.

A guided method for testing websites for cross-site scripting (XSS), where attacker-controlled text runs as code in another user's browser. It covers reflected, stored, and browser-side forms of XSS.

In plain words
What is it for?
It is for checking form fields, URLs, stored content, SVG and Markdown handling, redirects, and blind XSS callbacks from pages viewed later.
Why use it?
It helps distinguish harmlessly displayed or encoded input from input that actually causes a browser request, reducing false positives.

Skill for Claude Code

Written for Claude Code: SessionStart hook event.

Good fit It is for checking form fields, URLs, stored content, SVG and Markdown handling, redirects, and blind XSS callbacks from pages viewed later.

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Install with agentmods
npx agentmods add skills/encod3d-sec/torch/hunt-xss
Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

Any agent
npx skills add Encod3d-Sec/TORCH --skill hunt-xss
Clone the repo
git clone --depth 1 https://github.com/Encod3d-Sec/TORCH

Made for: Claude Code.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

agentmods badge for hunt-xss

README.md
[![agentmods](https://agentmods.dev/badge/skills/encod3d-sec/torch/hunt-xss/github.svg)](https://agentmods.dev/skills/encod3d-sec/torch/hunt-xss)
Your own site
<a href="https://agentmods.dev/skills/encod3d-sec/torch/hunt-xss"><img src="https://agentmods.dev/badge/skills/encod3d-sec/torch/hunt-xss/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

agentmods 80×15 button for hunt-xss

Your own site · 80×15
<a href="https://agentmods.dev/skills/encod3d-sec/torch/hunt-xss"><img src="https://agentmods.dev/badge/skills/encod3d-sec/torch/hunt-xss.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 45 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 1,701 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe. Third-party audits
  • NVIDIA SkillSpector pass 7 Sept 2026
How audits are shown
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5.1 $0.00045 $0.01701
Opus 5 $0.00023 $0.00851
Sonnet 5 $0.00009 $0.00340
Haiku 4.5 $0.00005 $0.00170

Measured 9d ago against content hash a61906dcf36f, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-09, from the pricing page.

Security

Grade A, and why

hunt-xss scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 9d ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

skills/hunt/hunt-xss/SKILL.md · 114 lines

How it starts

The opening of the file, as written. The whole thing — 114 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Hunt: XSS

Assumes hunt-core for the scope gate, two-account rule, confirmation gate, enumeration limits, stop conditions, wiki protocol, FIND output, and Deadends. Marker discipline (unique 8+ char canaries, check the baseline first) lives in hunt-core.

Wiki

qmd_query "XSS cross-site scripting DOM CSP bypass sanitizer" via wiki-search MCP

Hub: [[web-moc]] (live web index). Primary page: [[xss]]. Payload arsenals: wiki/payloads/{xss,prototype-pollution}.md. Related client-side vectors: [[dangling-markup]] (scriptless HTML-injection exfil when script tags are blocked), [[xssi]] (JSONP/script-inclusion info leak), [[browser-extension-attacks]] (content-script/message-passing injection).

Confirmation gate

NOT confirmation: payload URL-encoded or HTML-encoded in response, <script> appears as &lt;script&gt;, ASP.NET validator blocked <. IS confirmation: HTTP/DNS request to your unique Collaborator subdomain with browser User-Agent (Mozilla/Chrome).

When you plant a blind/stored XSS beacon, append a row to targets/<eng>/oob.md: | <token> | <sink url+param> | xss | <date> | waiting | | (columns: token | sink | class | planted | status | source, where token = your unique Burp Collaborator / interactsh label). The recon-capture hook auto-correlates incoming callbacks to flip the row to HIT and SessionStart surfaces HITs; a HIT row is the confirmation gate to scaffold the FIND. Do NOT claim a blind XSS without a HIT row.

Attack Surface Signals

High-value: admin panels (*/admin, */settings), payment flows, stored wikis/labels/tags, SSO/signin pages, SVG upload endpoints.

Approval / moderation workflow = the classic stored-XSS-to-privilege-escalation sink. Recognize it. When your submission "awaits review/approval by a moderator/admin" AND any field you control is rendered back in a privileged panel (a pending-registrations queue, a report/ticket viewer, a comment-moderation list, an order-approval screen), there is almost always a headless reviewer bot that opens that panel. That is a blind-XSS delivery you get for free: plant a cookie/session beacon in the field and the reviewer's session is exfiltrated -> replay their cookie -> you ARE the moderator/admin. The tell is often visible while authed as a lower role or as admin: if the panel shows a prior submission's raw markup (an unescaped username like <x> or sqltest'... sitting literally in the table), the sink is confirmed without even firing a payload -- that raw reflection IS the stored-XSS proof, do not walk past it. This is frequently the INTENDED path to the mid-tier (moderator) flag/role on a box that also has a heavier unintended route (LFI/RCE).

Read the full file on GitHub · 114 lines

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 9d ago First seen · 114 lines · 45 tokens per session scan A a61906dcf36f

Subscribe to this mod's changes

hunt-xss is a skill published in the GitHub repository Encod3d-Sec/TORCH (318 stars, last pushed 8d ago), licensed MIT. It adds 45 tokens to every session and 1,701 once invoked, about $0.0002 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.

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