New: 98,000+ skills indexed from GitHub repos with 100+ stars · every skill safety-checkedBrowse top skillsTop skills
Esc to closeBrowse all skills
Submit a skillBrowse skills
Submit a skillBrowse skills

Agent skill

Hunt HTTP Smuggling

by sickn33 in sickn33/agentic-awesome-skills

Hunt HTTP request smuggling (CL.TE, TE.CL, H2.CL, H2.TE). An agent skill from sickn33/agentic-awesome-skills.

MITAuto-check passed

Install Hunt HTTP Smuggling

skills CLI
$ npx skills add sickn33/agentic-awesome-skills --skill hunt-http-smuggling -a claude-code

Project install by default; add -g for ~/.claude/skills/.

GitHub CLI
$ gh skill install sickn33/agentic-awesome-skills hunt-http-smuggling --agent claude-code

Project scope by default; add --scope user for a personal install. Needs GitHub CLI 2.90.0 or later (public preview).

Manual copy
$ git clone --depth 1 https://github.com/sickn33/agentic-awesome-skills.git skills-src && mkdir -p .claude/skills && cp -r skills-src/skills/hunt-http-smuggling .claude/skills/hunt-http-smuggling && rm -rf skills-src

Use ~/.claude/skills/ instead of .claude/skills for a personal install. The folder must contain SKILL.md.

Claude Code skills documentation · loads skills from .claude/skills/

Facts

Skill name
hunt-http-smuggling
GitHub stars
47k
Used in
1 other repo
Token cost
~2.2k tokens
SKILL.md length
962 words
Files
2 (incl. references)
Skills in repo
1,354
Repo updated
First seen
Licence
MIT

At a glance

Hunt HTTP request smuggling (CL.TE, TE.CL, H2.CL, H2.TE). An agent skill from sickn33/agentic-awesome-skills.

  • SKILL.md covers HTTP REQUEST SMUGGLING, Target-Suitability Matrix…, Related Skills & Chains and When to Use, plus 1 more section
  • Calls curl

What it does

Hunt HTTP Smuggling is an agent skill from sickn33/agentic-awesome-skills. Hunt HTTP request smuggling (CL.TE, TE.CL, H2.CL, H2.TE).

Its SKILL.md is about 2.2k tokens, which your agent loads only when the skill is triggered. The skill folder holds 2 other files, including reference files (for example `references/phase2h-smuggling-cachepoison.md`). Compatibility notes: Requires explicit written authorization for a target scope plus the relevant testing tools for this technique. Docs-only; helper scripts and commands not…

The repository describes itself as: AAS Core is the local, agent-first control plane for complete catalog discovery, agent-owned selection, stack validation, and planning, backed by 2,400+ agentic skills. Includes… The licence is MIT.

Example prompts

  • “/hunt-http-smuggling”

Requirements

  • Python 3
  • Compatibility (from SKILL.md): Requires explicit written authorization for a target scope plus the relevant testing tools for this technique. Docs-only; helper scripts and commands not bundled.

What it can do on your machine

Read from SKILL.md and the folder at commit ec02547. It shows what the files ask for, not the result of running them.

  • Tool permissions

    Pre-approves nothing: there is no allowed-tools line, so your agent's usual permission prompts apply.

    From allowed-tools in the SKILL.md frontmatter.

  • Runs code

    Shell commands in SKILL.md call:

    • curl

    From the folder's file list and the shell code blocks in SKILL.md.

  • Network

    Links to these hosts (documentation or services it may open):

    • github.com

    From URLs in SKILL.md, links to its own repository left out.

  • Credentials

    Names no API keys, tokens, secrets or passwords.

    From names ending in _API_KEY, _TOKEN, _SECRET, _KEY or _PASSWORD in SKILL.md.

  • Compatibility

    Requires explicit written authorization for a target scope plus the relevant testing tools for this technique. Docs-only; helper scripts and commands not bundled.

    From compatibility in the SKILL.md frontmatter.

Context cost

Hunt HTTP Smuggling loads about 2.2k tokens when it runs, and up to ~4.3k if it reads all its reference files. Until then it costs about 19 tokens; SKILL.md has 962 words of instructions outside code blocks.

Always · name and description, kept in context so the agent knows when to use it
~19
When it runs · the whole SKILL.md, loaded when a task matches
~2.2k
With references · SKILL.md plus every file in references/, read only if the agent opens them
~4.3k

Estimates: characters ÷ 4, the usual rule of thumb; real counts depend on the model's tokenizer. Scripts and assets cost tokens only if the agent reads them.

Safety

Auto-check passed

The automated check found no risky patterns in SKILL.md.

Automated static check — not a guarantee. Review scripts before installing. It scans the text of SKILL.md for risky patterns (piping downloads into a shell, reading credential files, hidden Unicode, destructive commands); files beside SKILL.md are not scanned.

SKILL.md

The full file from sickn33/agentic-awesome-skills at commit ec02547, republished under its MIT licence (© sickn33). 962 words, ~2,238 tokens.

Download SKILL.mdSave it as .claude/skills/hunt-http-smuggling/SKILL.md (or your agent's skills folder). This skill also uses 1 other file; get the full folder from GitHub.
name
hunt-http-smuggling
description
Hunt HTTP request smuggling (CL.TE, TE.CL, H2.CL, H2.TE).
compatibility
Requires explicit written authorization for a target scope plus the relevant testing tools for this technique. Docs-only; helper scripts and commands not bundled.
category
security
risk
offensive
source
https://github.com/elementalsouls/Claude-BugHunter
source_repo
elementalsouls/Claude-BugHunter
source_type
community
date_added
2026-09-20
license
MIT
license_source
https://github.com/elementalsouls/Claude-BugHunter/blob/main/LICENSE
sources
hackerone_public, cve_database, portswigger_research, public_research
report_count
12

⚠️ AUTHORIZED USE ONLY This skill is for educational purposes or authorized security assessments only. You must have explicit, written permission from the system owner before using this tool. Misuse of this tool is illegal and strictly prohibited.

Mandatory confirmation gate Before running any command that probes, exploits, changes, persists on, extracts data from, or attempts credential access against a target:

  1. Ask the user to state the exact target URL, IP, account, or resource.
  2. Ask the user to confirm written authorization and the permitted scope.
  3. Show the exact command(s) and explain their expected effect.
  4. Wait for explicit confirmation in the current conversation.

Without that confirmation, remain read-only and provide defensive guidance only. Prefer a sandbox, disposable VM, or controlled lab.

HTTP REQUEST SMUGGLING

Lowest dup rate. $5K–$30K. PortSwigger research by James Kettle.

CL.TE (Content-Length front, Transfer-Encoding back)
http
POST / HTTP/1.1
Content-Length: 13
Transfer-Encoding: chunked

0

SMUGGLED
Detection
1. Burp extension: HTTP Request Smuggler
2. Right-click request → Extensions → HTTP Request Smuggler → Smuggle probe
3. Manual timing: CL.TE probe + ~10s delay = backend waiting for rest of body
Impact Chain
Poison next request → access admin as victim
Steal credentials → capture victim's session
Cache poisoning → stored XSS at scale

Target-Suitability Matrix (2026 reality check)

The classic CL.TE / TE.CL payloads are NOT universally exploitable in 2026. Modern proxies are RFC 9112 strict by default. Fingerprint the front-end BEFORE investing time.

Front-endCL.TETE.CLH2.CLH2.TENotes
Nginx ≥ 1.21NONOpartial (H2 ingress)partialRFC-strict; rejects CL+TE with HTTP 400. Verified locally on Nginx 1.27 — all 9 documented variants killed by front-end (docs/verification/phase2h-smuggling-cachepoison.md).
Caddy 2.xNONO——Hardened by default
Envoy ≥ 1.20NONOpartialpartialHardened in most paths
HAProxy ≤ 2.4✓✓——Vulnerable, see CVE-2021-40346
AWS ALB + specific upstreampartialpartial✓✓Several disclosed-paid reports 2022-2024
Cloudflare → S3 / Lambda chains——✓✓H2-downgrade attacks remain viable
Older F5 BIG-IP (TMM < 16)✓———Vendor advisories
Citrix ADC / NetScaler (older firmware)✓✓——Disclosed in 2020-2022
Squid 3.x✓———Older deployments
Apache Traffic Server (older)✓✓✓✓PortSwigger research
Apache mod_proxy_ajp → Tomcat————Cross-protocol HTTP→AJP desync (CVE-2022-26377); smuggled request is opaque to the WAF and reaches internal AJP admin/status paths that lack the external auth controls
Custom Python / Go proxies✓✓——Frequently miss RFC enforcement
Operator fingerprint quick-check
bash
curl -sI https://target/ | grep -i "Server:"
  • nginx/1.21+, Caddy, envoy → CL/TE classic is dead — pivot to H2.CL/H2.TE if the front-end speaks HTTP/2, or look for legacy proxies upstream
  • HAProxy, header points to AWS/CDN → run the full payload matrix
  • No Server header → assume hardened, but run a single quick space-before-colon probe; if it doesn't 400, dig deeper
H2.CL / H2.TE (the modern dominant vector)

H2-downgrade smuggling attacks rely on the front-end speaking HTTP/2 to the client and HTTP/1.1 to origin. The downgrade introduces CL/TE confusion because HTTP/2's frame-length headers don't survive the conversion cleanly. Most CDN+origin chains in 2024-2026 use this exact topology.

Tools that send HTTP/2 raw frames (Burp Pro's HTTP Request Smuggler extension, h2csmuggler, smuggler.py) are the right starting point against CDN-fronted targets. Avoid HTTP/1.1-only test clients (curl, raw sockets) against H2-front-ended targets — you'll send the wrong protocol entirely.

Mass credential harvesting — the "collector gadget"

The highest-impact smuggling outcome needs no per-victim interaction. Instead of blindly poisoning the queue, smuggle a request aimed at a back-end handler that echoes the full request — a search endpoint that reflects headers, or a redirect that mirrors the request line. The next victim's headers (Cookie, Authorization, X-Access-Token) get attributed to your smuggled request, and the reflecting handler returns them in a response you read. Repeated on a busy keep-alive socket, this harvests live credentials from arbitrary users at scale — and it works even through a CDN (Akamai/Cloudflare) when the CDN↔origin hop desyncs. Chains to hunt-ato.

Show full SKILL.md (420 more words)Show less
  • hunt-cache-poison — Smuggling + cache is the canonical critical chain; one smuggled request becomes the cached response for every subsequent victim. Chain primitive: CL.TE smuggle a request whose response body contains attacker HTML/JS → front-end cache stores it under a popular URL (/, /login) → de-sync poisoning where the smuggled request becomes the cached response for the next N victims, persisting for the cache TTL.
  • hunt-auth-bypass — Smuggling reaches internal-only routes that the front-end WAF/auth-proxy filters out. Chain primitive: smuggle GET /admin/users HTTP/1.1 past the front-end ACL that blocks external /admin/* → backend processes the smuggled request as if from a trusted internal source → bypass front-end auth by smuggling internal-routed request → admin data in the response queue.
  • hunt-idor — Smuggling attaches the NEXT user's session cookies to an attacker-controlled request path. Chain primitive: smuggle GET /api/me HTTP/1.1 with no cookies → backend pairs it with the next legitimate user's incoming connection cookies → victim's session cookie attached to attacker's smuggled request → attacker reads the response containing victim's PII/tokens.
  • hunt-xss — Smuggling injects XSS payloads into the response stream of the next victim without ever appearing in a URL parameter. Chain primitive: smuggled request body contains reflected payload that the backend renders into the next response in the queue → next visitor to / receives attacker HTML inline → reflected XSS at every visitor without any URL parameter visible to them or to logs.
  • security-arsenal — Reach for the smuggling payload bank (CL.TE / TE.CL / TE.TE obfuscations, H2.CL downgrade probes, h2csmuggler one-liners, Burp HTTP Request Smuggler extension config) and the time-delay confirmation template before manual hex-editing.
  • triage-validation — Run the Pre-Severity Gate before claiming Critical: the smuggled-request effect MUST land on a request issued by a different client/session, not your own follow-up. A timing delta in your own browser alone is parser disagreement, not exploitable smuggling.

When to Use

  • You have explicit, written authorization to assess the target in scope, and the task matches this skill's vulnerability class or technique within a bug-bounty or penetration-test engagement.
  • You need the recon, exploitation, or validation workflow described below — executed strictly inside the approved scope.

Limitations

  • Authorized scope only: the confirmation gate above is mandatory before any probing, exploitation, or credential-access command.
  • Docs-only import: upstream helper scripts, commands, engine, and research assets are not bundled; reinstall tooling from the source repo when needed.
  • Validate every finding (see triage-validation) before reporting; report via report-writing. Prefer a sandbox, disposable VM, or controlled lab.
Example
bash
# Read-only first step; confirm scope before anything active.
cat scope.txt  # target list from the authorized engagement brief

Adapted from elementalsouls/Claude-BugHunter (MIT); frontmatter, When to Use/Limitations, and safety boundaries added for upstream compliance. Docs-only import: executable helpers, commands, engine, and research assets not bundled.

© sickn33, MIT. Rendered from Markdown: HTML in the file is shown as text, images as links, and headings moved down two levels. Raw file

Files

SKILL.md and 1 other file (references) in skills/hunt-http-smuggling of sickn33/agentic-awesome-skills.

  • SKILL.md
  • references/phase2h-smuggling-cachepoison.md

Open the folder on GitHubat commit ec02547

Used in 1 other repository

We found 5 copies of this SKILL.md (exact, near-identical or edited) in other folders, from 1 other GitHub owner. This page covers the copy in sickn33/agentic-awesome-skills, which our catalogue first saw on October 7, 2026.

Compare with similar skills

Hunt HTTP Smuggling next to the 5 skills that share the most tags, products or categories with it. Stars are the repository's; “used in” counts other GitHub owners with a copy.

Hunt HTTP Smuggling compared with similar skills
SkillStarsUsed inTokensAuto-checkLicenceRepo updated
Hunt HTTP Smuggling this skillsickn33/agentic-awesome-skills47k1 repos~2.2kAutomated safety check: PassMIT
Hunt HTTP Smugglingelementalsouls/Claude-BugHunter4.8k—~1.8kAutomated safety check: PassMIT
Exploiting HTTP Request Smugglingmukul975/Anthropic-Cybersecurity-Skills34k—~2.8kAutomated safety check: PassApache-2.0
Hunt SmugglingEncod3d-Sec/TORCH329—~1.6kAutomated safety check: PassMIT
HTTP To Httpsthedaviddias/Front-End-Checklist74k—~512Automated safety check: PassMIT
HTTP Requeststhedaviddias/Front-End-Checklist74k—~415Automated safety check: PassMIT

Similar skills

  • Hunt HTTP Smuggling

    elementalsouls/Claude-BugHunter

    Hunt HTTP request smuggling (CL.TE, TE.CL, H2.CL, H2.TE). An agent skill from elementalsouls/Claude-BugHunter.

    4.8k GitHub stars~1.8k tokensUpdated yesterday
    DevOps & CloudAuto-check passed

  • Exploiting HTTP Request Smuggling

    mukul975/Anthropic-Cybersecurity-Skills

    Detects and exploits HTTP request smuggling caused by Content-Length/Transfer-Encoding parsing discrepancies between front-end and back-end servers, using Burp Suite Repeater (auto Content-Length…

    34k GitHub stars~2.8k tokensUpdated 1 mo ago
    DevOps & CloudAuto-check passed

  • Hunt Smuggling

    Encod3d-Sec/TORCH

    HTTP request smuggling / desync hunting - CL.TE, TE.CL, TE.TE, CL.0, and HTTP/2 downgrade.

    329 GitHub stars~1.6k tokensUpdated 1 mo ago
    SecurityAuto-check passed

  • HTTP To Https

    thedaviddias/Front-End-Checklist

    A skill your agent uses when checking whether a web server is configured to redirect all HTTP traffic to HTTPS.

    74k GitHub stars~512 tokensUpdated 2 days ago
    Auto-check passed

  • HTTP Requests

    thedaviddias/Front-End-Checklist

    A skill your agent uses when auditing slow page loads, heavy assets, or rendering delays related to Minimize HTTP requests.

    74k GitHub stars~415 tokensUpdated 2 days ago
    Frontend & DesignAuto-check passed

  • Threat Hunting

    zhaoxuya520/reverse-skill

    A skill your agent uses for blue-team threat hunting, detection engineering with Sigma/YARA, SIEM query design, and incident detection validation.

    40k GitHub starsUsed in 2 repos~344 tokens
    SecurityAuto-check: warnings

More from sickn33/agentic-awesome-skills

All 1,354 skills in this repo

  • Liuguang Banlan UI

    sickn33/agentic-awesome-skills

    Implements an interface in one of two named color modes, iridescent white or colorful black, from a parameterized starter that reports measured color intensity.

    47k GitHub starsUsed in 1 repo~2.5k tokens
    Auto-check passed

  • User Thoughts Memory

    sickn33/agentic-awesome-skills

    Saves a user's project decisions, rules and preferences into a project-local mdbase so later sessions and other agents can recover the intent.

    47k GitHub starsUsed in 1 repo~2.5k tokens
    Auto-check passed

  • Using LWC Memory and Graphs

    sickn33/agentic-awesome-skills

    Keeps project decisions, research and verified results available across coding-agent sessions through LWC memory, a document Wiki graph and a CodeGraph code index.

    47k GitHub starsUsed in 1 repo~2k tokens
    Auto-check passed

  • Find Complementary Founders

    sickn33/agentic-awesome-skills

    Guides an agent through assessing its own owner for cofounder fit, publishing an approved profile, and ranking complementary profiles other agents published for their owners.

    47k GitHub starsUsed in 1 repo~4.8k tokens
    Auto-check passed

  • Cline Pilot

    sickn33/agentic-awesome-skills

    Acts as a proxy for the Cline CLI, dispatching coding tasks one at a time, monitoring runs by hard evidence, relaying decisions to you and learning per-project preferences.

    47k GitHub starsUsed in 1 repo~4.6k tokens
    Auto-check passed

  • Content Creator

    sickn33/agentic-awesome-skills

    Drafts and reviews audience-specific content from supplied brand examples, with local scripts for brand voice and SEO diagnostics, channel templates and a content calendar.

    47k GitHub starsUsed in 1 repo~2.5k tokens
    Auto-check passed

Questions about Hunt HTTP Smuggling

What does Hunt HTTP Smuggling do?

Hunt HTTP request smuggling (CL.TE, TE.CL, H2.CL, H2.TE). An agent skill from sickn33/agentic-awesome-skills. Hunt HTTP Smuggling is an agent skill from sickn33/agentic-awesome-skills.TE).

How do I install Hunt HTTP Smuggling in Claude Code?

Run `npx skills add sickn33/agentic-awesome-skills --skill hunt-http-smuggling -a claude-code`. Or copy the skill folder (skills/hunt-http-smuggling in sickn33/agentic-awesome-skills) into .claude/skills/hunt-http-smuggling in your project. Claude Code loads it when a task matches its description.

How do I install Hunt HTTP Smuggling in Codex?

Run `npx skills add sickn33/agentic-awesome-skills --skill hunt-http-smuggling -a codex`. Or copy the skill folder (skills/hunt-http-smuggling in sickn33/agentic-awesome-skills) into .agents/skills/hunt-http-smuggling in your project. Codex loads it when a task matches its description.

Can I use Hunt HTTP Smuggling in Cursor, Gemini CLI or GitHub Copilot?

Cursor, Gemini CLI, GitHub Copilot and OpenCode also load SKILL.md folders. With the skills CLI, run `npx skills add sickn33/agentic-awesome-skills --skill hunt-http-smuggling -a cursor` (or -a gemini-cli, github-copilot or opencode for the others). To copy it by hand, put the folder in .cursor/skills/hunt-http-smuggling, .gemini/skills/hunt-http-smuggling, .github/skills/hunt-http-smuggling and .opencode/skills/hunt-http-smuggling in your project.

What does Hunt HTTP Smuggling need to run?

Going by SKILL.md and its folder, Hunt HTTP Smuggling needs the command-line tools its instructions call (curl). Our summary lists: Python 3. Compatibility (from SKILL.md): Requires explicit written authorization for a target scope plus the relevant testing tools for this technique. Docs-only; helper scripts and commands not bundled..

Does Hunt HTTP Smuggling access the network?

SKILL.md names 1 domain. As links in the text: github.com. This is read from the text; nothing was executed.

Is Hunt HTTP Smuggling safe to install?

Our automated static check of SKILL.md found no risky patterns, such as piping downloads into a shell, reading credential files or hidden Unicode. It is not a guarantee. Review the folder before installing.

What licence does Hunt HTTP Smuggling use?

Hunt HTTP Smuggling is published under the MIT licence (declared in SKILL.md). It allows redistribution, so the full SKILL.md is shown on this page.

How many tokens does Hunt HTTP Smuggling use?

About 2.2k tokens (SKILL.md is roughly 9k characters). Agents keep only the skill's name and description in context until a task matches; then they load SKILL.md in full. Its references folder adds about 2.1k tokens, read only when the agent opens those files.

What are the alternatives to Hunt HTTP Smuggling?

Skills that share tags, products or a category with Hunt HTTP Smuggling: Hunt HTTP Smuggling (elementalsouls/Claude-BugHunter, 4.8k stars), Exploiting HTTP Request Smuggling (mukul975/Anthropic-Cybersecurity-Skills, 34k stars), Hunt Smuggling (Encod3d-Sec/TORCH, 329 stars) and HTTP To Https (thedaviddias/Front-End-Checklist, 74k stars). The comparison table on this page puts their stars, adoption, token cost, safety result and licence side by side.

Who maintains Hunt HTTP Smuggling?

sickn33 (a GitHub user) maintains it in sickn33/agentic-awesome-skills, which has 47,343 GitHub stars. The repository holds 1,354 skills in this directory. The repository was last updated on October 7, 2026.

Source: sickn33/agentic-awesome-skills on GitHub. Facts on this page come from the repository at the commit we read; the author's words are quoted as theirs.