request-smuggling

Detect HTTP request smuggling vulnerabilities from message framing desynchronization.

96|1|Updated Jun 4, 2026

Search Tags:#penetration testing #web security #reverse proxy #http request smuggling #desynchronization #cl.te #te.cl

Ready to run

npx skills add https://github.com/langbyyi/CyberStrikeAI-SRC --skill request-smuggling-langbyyi

💬 Prompt for ChatGPT / Claude Chat▼

Please help me install this Agent Skill.
Skill: request-smuggling
Source: https://github.com/langbyyi/CyberStrikeAI-SRC/tree/main/skills/request-smuggling
Command: npx skills add https://github.com/langbyyi/CyberStrikeAI-SRC --skill request-smuggling-langbyyi

SYSTEM DOCUMENTATION & REQUIREMENTS

What problem does it solve?

This Skill addresses undetected HTTP request smuggling vulnerabilities caused by message framing disagreements between front proxies, CDNs, load balancers and origin servers, which can lead to WAF bypasses, cache poisoning, and authentication boundary breaches.

Core Features & Use Cases

Supports testing for CL.TE, TE.CL, and TE.TE obfuscation variants of classic HTTP/1.1 request smuggling.
Covers HTTP/2 downgrade smuggling and client-side desync via browser fetch pipelines.
Includes tool-assisted fuzzing guidance and a detection decision tree for structured security assessments. Use case: Penetration testers evaluating web applications behind reverse proxies or CDNs can use this Skill to identify desynchronization flaws that bypass access controls.

Quick Start

Use the request-smuggling skill to run a CL.TE probe against the target web application behind a reverse proxy to check for message framing desynchronization.

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 message framing desynchronization happen?▼

HTTP request smuggling occurs when front proxies and origin servers disagree on message framing boundaries, allowing hidden requests to bypass WAFs, poison caches, and breach authentication boundaries. This desynchronization exploits differing interpretations of Content-Length and Transfer-Encoding headers.

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

Detect CL.TE and TE.CL request smuggling by probing reverse proxy topologies with tool-assisted fuzzing. Use a structured detection decision tree to identify message framing disagreements between front-end CDNs and back-end origin servers.

Can I test for HTTP/2 downgrade smuggling and client-side browser fetch desync?▼

Yes, you can test for HTTP/2 downgrade smuggling and client-side desync via browser fetch pipelines. This assessment identifies desynchronization flaws occurring when HTTP/2 connections are downgraded to HTTP/1.1 across reverse proxy topologies.

Does this request smuggling detection approach cover TE.TE obfuscation variants?▼

Yes, this request smuggling detection covers TE.TE obfuscation variants alongside CL.TE and TE.CL. It provides tool-assisted fuzzing procedures to identify these message framing desynchronization flaws between reverse proxies and origin servers.

When do I need to test for HTTP request smuggling vulnerabilities?▼

Test for HTTP request smuggling vulnerabilities when evaluating web applications deployed behind reverse proxies, CDNs, or load balancers. It is crucial for finding desynchronization flaws that bypass access controls and enable cache poisoning.