crlf-injection

Detect CRLF injection vulnerabilities in HTTP headers, cookies, and log files.

Updated Jun 11, 2026

Search Tags:#web security #vulnerability detection #http response splitting #crlf injection #security mitigation

Ready to run

npx skills add https://github.com/utsavthakur/agenticskills --skill crlf-injection-utsavthakur

💬 Prompt for ChatGPT / Claude Chat▼

Please help me install this Agent Skill.
Skill: crlf-injection
Source: https://github.com/utsavthakur/agenticskills/tree/main/crlf-injection
Command: npx skills add https://github.com/utsavthakur/agenticskills --skill crlf-injection-utsavthakur

SYSTEM DOCUMENTATION & REQUIREMENTS

💡 This Skill includes scripts (resource) and references (resource) components.

What problem does it solve?

This Skill identifies and mitigates CRLF injection vulnerabilities in web applications, protecting against attacks that could lead to HTTP response splitting and other security risks.

Core Features & Use Cases

CRLF Detection: Identifies CRLF injection points in HTTP headers, cookies, and log files.
Exploit Prevention: Blocks common CRLF injection attacks and provides bypass strategies.
Use Case: Ensure your web applications are secure against CRLF injection attacks that can lead to XSS, session fixation, and cache poisoning.

Quick Start

Use the crlf-injection skill to scan your web application for CRLF injection vulnerabilities.

Frequently Asked Questions about crlf-injection

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

FAQPage Schema

What is CRLF injection and how does it affect web applications?▼

CRLF injection is a web security vulnerability where attackers inject carriage return and line feed sequences into HTTP headers, cookies, or log files. This can lead to HTTP response splitting, XSS, session fixation, and cache poisoning in web applications.

How do I detect CRLF injection vulnerabilities in HTTP headers and cookies?▼

You can detect CRLF injection by monitoring HTTP headers, cookies, and log files for malicious CRLF sequences. Scanning your web application identifies these injection points to prevent exploitation and secure user data.

How can I prevent HTTP response splitting attacks caused by CRLF sequences?▼

Prevent HTTP response splitting by implementing security mitigations that block CRLF sequences in HTTP headers and cookies. This involves scanning for injection points and applying bypass strategies to secure web applications against CRLF-based attacks.

Does this CRLF injection scanner work without external dependencies?▼

Yes, this vulnerability detection tool operates with no external dependencies. It uses built-in scripts and references to identify and mitigate CRLF injection points in your web application's headers, cookies, and logs.

What is the best way to mitigate CRLF injection to prevent XSS and cache poisoning?▼

The best way to mitigate CRLF injection is to scan your web application for injection points and apply targeted security mitigations. This blocks CRLF sequences, preventing downstream attacks like XSS, session fixation, and cache poisoning.

When should I scan my web application for CRLF injection vulnerabilities?▼

You should scan for CRLF injection vulnerabilities whenever you process user input in HTTP headers, cookies, or log files. Regular scanning identifies injection points and provides bypass strategies to secure web applications against CRLF-based attacks.