request-smuggling

Identify and test HTTP request smuggling and desync vulnerabilities across proxies, CDNs, and origin servers.

1.6k|204|Updated Apr 7, 2026
One-click install
npx skills add https://github.com/yaklang/hack-skills --skill request-smuggling-yaklang
Or copy as Structured Prompt for Agent▼
Please help me install this Agent Skill.
Skill: request-smuggling
Source: https://github.com/yaklang/hack-skills/tree/main/skills/request-smuggling
Command: npx skills add https://github.com/yaklang/hack-skills --skill request-smuggling-yaklang

SYSTEM DOCUMENTATION & REQUIREMENTS

What problem does it solve?

HTTP request smuggling and desynchronization testing exposes and assesses misinterpretations of HTTP message framing between front-end proxies and origin servers, enabling safer discovery of boundary-disagreement issues.

Core Features & Use Cases

  • Comprehensive technique coverage: CL.TE, TE.CL, TE.TE, H2 downgrade, and client-side desync methods.
  • Structured playbook: step-by-step probes, safe testing guidelines, and containment strategies for proxy/CDN topologies.
  • Use Case: Assess a web stack behind a CDN to reveal where request boundaries are inconsistently parsed, leading to potential bypass or cache poisoning.

Quick Start

Perform the CL.TE probe on a test target within authorized scope to confirm boundary misinterpretation.

Frequently Asked Questions about request-smuggling

High-intent search queries and answers about installing and using this skill.

FAQPage Schema
What is HTTP request smuggling and how does desync testing expose boundary issues?▼

HTTP request smuggling occurs when front-end proxies and origin servers disagree on message framing boundaries. Desync testing exposes this by sending ambiguous Content-Length and Transfer-Encoding headers to identify where request parsing misinterpretations occur.

How do I test for CL.TE and TE.CL request smuggling vulnerabilities?▼

You test CL.TE and TE.CL vulnerabilities by executing structured probes that send conflicting Content-Length and Transfer-Encoding headers. This identifies whether the front-end or back-end server prioritizes the wrong header, causing request boundary desynchronization.

Can I perform HTTP request smuggling testing on targets behind a CDN and proxy?▼

Yes, HTTP request smuggling testing applies to web stacks behind CDNs and proxies. It assesses front-end versus back-end boundary handling across proxy topologies to reveal inconsistent request parsing that can lead to bypass or cache poisoning.

Does HTTP request smuggling testing cover H2 downgrade and client-side desync techniques?▼

Yes, HTTP request smuggling testing covers H2 downgrade and client-side desync techniques. It assesses HTTP/2 protocol downgrades and client-side desynchronization methods alongside standard CL.TE, TE.CL, and TE.TE attack vectors across enterprise networks.

What is the best way to safely probe for HTTP desync vulnerabilities in authorized environments?▼

The best way to safely probe for HTTP desync vulnerabilities is using authorization-respecting probes with step-by-step guidance. This provides containment strategies and safe testing guidelines to assess proxy and CDN topologies without causing unintended disruption.