CRLFuzz

CRLFuzz is a specialized tool designed to detect CRLF (Carriage Return Line Feed) vulnerabilities, which can lead to HTTP response splitting and other web-based attacks. It performs fuzzing on target URLs to identify injection points where CRLF sequences can manipulate server responses.

Use cases include penetration testing web applications, auditing HTTP headers, and identifying misconfigurations in web servers that allow CRLF injection. The tool is particularly useful for security researchers and pentesters scanning for these specific vulnerabilities at scale.

Developers emphasize caution, noting users are responsible for their actions and the tool assumes no liability for misuse or damage.

CRLFuzz fuzzes HTTP requests to target URLs or lists of URLs by injecting CRLF sequences into various parts of the request, such as headers or data payloads. It uses concurrency for speed, defaulting to 20 threads, and supports custom methods, headers, proxies, and data. The tool analyzes responses for signs of CRLF injection success, like unauthorized header injection or response splitting.