CRLF Injection Attack

Anandhu Krishnan
Published on
14 May 2024


A malicious actor can exploit this vulnerability by injecting carriage return and line feed characters into user input, allowing them to manipulate the HTTP request. This could lead to unintended consequences such as setting arbitrary cookies or response headers.


To mitigate this vulnerability, ensure that all user-submitted data is properly sanitized and validated. Implement strict input validation to prevent malicious actors from injecting CRLF sequences.

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Written by
Anandhu Krishnan
Anandhu Krishnan
Lead Engineer
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