crlf-injection

Identify and demonstrate CRLF injection vulnerabilities in HTTP headers and response bodies.

120|8|Updated Jun 2, 2026
One-click install
npx skills add https://github.com/Prohao42/aimy-skill --skill crlf-injection-prohao42
Or copy as Structured Prompt for Agent
Please help me install this Agent Skill.
Skill: crlf-injection
Source: https://github.com/Prohao42/aimy-skill/tree/main/ai-mian/hack-skills/skills/crlf-injection
Command: npx skills add https://github.com/Prohao42/aimy-skill --skill crlf-injection-prohao42

SYSTEM DOCUMENTATION & REQUIREMENTS

💡 This Skill includes scripts (resource) components.

What problem does it solve?

This Skill identifies and demonstrates how to exploit CRLF injection vulnerabilities in web applications, allowing for the manipulation of HTTP headers and response bodies.

Core Features & Use Cases

  • CRLF Detection: Identifies instances where CRLF can be injected into HTTP headers, Location redirects, Set-Cookie values, or log files.
  • Exploitation Techniques: Demonstrates various exploitation scenarios, including header injection, response body injection, XSS escalation, cache poisoning, and encoding bypass.
  • Real-World Chains: Provides examples of real-world exploitation chains, such as CRLF + Session Fixation and CRLF → XSS via Double CRLF Body Injection.

Quick Start

Run the crlf-injection skill to test for CRLF injection vulnerabilities in a target URL.

Frequently Asked Questions about crlf-injection

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

FAQPage Schema
How do I test a web application for CRLF injection vulnerabilities?

To test for CRLF injection, you inject carriage return and line feed characters into HTTP headers, Location redirects, or Set-Cookie values to see if they manipulate the response. This skill detects those vulnerabilities and identifies common attack vectors automatically.

Can CRLF injection be escalated to cross-site scripting or cache poisoning?

Yes, CRLF injection can escalate to XSS via double CRLF body injection and enable cache poisoning by injecting malicious headers. This skill demonstrates real-world exploitation chains including session fixation and XSS escalation scenarios.

What HTTP headers are most vulnerable to CRLF injection attacks?

Location redirects and Set-Cookie values are common targets for CRLF injection attacks. This skill identifies instances where CRLF can be injected into these headers, log files, and other HTTP response headers to manipulate web application behavior.

How do I bypass encoding filters when exploiting CRLF injection?

Encoding bypass techniques for CRLF injection involve using alternative character encodings to evade input validation filters. This skill demonstrates various encoding bypass methods and exploitation scenarios for web applications with filtering mechanisms.

Do I need knowledge of HTTP response headers to detect CRLF injection?

Yes, detecting CRLF injection requires knowledge of HTTP response headers and common attack vectors. This skill focuses on HTTP header manipulation and response body injection, making header knowledge essential for identifying and exploiting these vulnerabilities.