Vulnerability field guide

CRLF Injection

A carriage return and a line feed are all it takes to inject headers, forge cookies and poison caches. Here is how CRLF injection leads to HTTP response splitting, and how to shut it down.

1 article 5 min total Overview to advanced techniques

InjectionOverview %0d%0aSet-Cookie: session=1

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CRLF Injection5 min read

CRLF Injection: How Two Invisible Characters Split an HTTP Response

A carriage return and a line feed are all it takes to inject headers, forge cookies and poison caches. Here is how CRLF injection leads to HTTP response splitting, and how to shut it down.

Read the overview