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<!-- Licensed under AGPL-3.0 — see LICENSE file for details. -->
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---
name: testing-crlf-injection
description: >-
  Test for CRLF injection vulnerabilities to inject HTTP headers, split responses, perform XSS via header injection, and poison web caches through response splitting.
domain: cybersecurity
subdomain: bug-bounty
tags:
  - crlf
  - response-splitting
  - header-injection
  - cache-poisoning
version: "1.0"
author: defconxt
license: AGPL-3.0
metadata:
  mitre-attack: ["T1190"]
  frameworks: ["MITRE ATT&CK", "OWASP"]
  tools: ["burpsuite", "crlfuzz", "curl"]
---

# Testing Crlf Injection

## Overview

Test for CRLF injection vulnerabilities to inject HTTP headers, split responses, perform XSS via header injection, and poison web caches through response splitting.

## Prerequisites

| Tool / Requirement | Details |
|---|---|
| `burpsuite` | Security tooling |
| `crlfuzz` | Security tooling |
| `curl` | Security tooling |
| Burp Suite, crlfuzz, target application with header reflection | Environment requirement |

## Quick Reference

```bash
# Quick start commands
node scripts/agent.js --help
node scripts/agent.js scan --url https://target.com
```

## Workflow

### Step 1: Scan for CRLF Points

```bash
node scripts/agent.js scan --url https://target.com
```

### Step 2: Test Header Injection

```bash
curl -v 'https://target.com/redirect?url=http://evil.com%0d%0aInjected-Header:true'
```

### Step 3: Exploit Response Splitting

```bash
node scripts/agent.js exploit --url https://target.com --param redirect --payload xss
```


## Verification

- **Verify CRLF scan**: `node scripts/agent.js scan --url https://target.com`
- **Confirm injection**: `node scripts/agent.js exploit --url https://target.com --param redirect --payload xss`

## References

- MITRE ATT&CK: T1190
- Frameworks: MITRE ATT&CK, OWASP
- Tools: burpsuite, crlfuzz, curl
