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HTTP Header Abuse using CRLF Injection

HTTP Header Abuse using CRLF Injection

This test examines the vulnerability of CRLF injection in HTTP headers, specifically focusing on the manipulation of query parameters through the abuse of line breaks.

CRLF Injection

Business Logic

"In a CRLF injection attack, the attacker inserts the carriage return and linefeed characters into user input to trick the server, the web application, or the user into thinking that an object has terminated and another one has started By exploiting a CRLF injection, an attacker can also insert HTTP headers which could be used to defeat security mechanisms such as a browser’s XSS filter or the same-origin-policy. This allows malicious actors to obtain sensitive information like CSRF tokens. Attackers can also set cookies which could be exploited by logging the victim into the attacker’s account or used to exploit otherwise unexploitable cross-site scripting vulnerabilities."

"In a CRLF injection attack, the attacker inserts the carriage return and linefeed characters into user input to trick the server, the web application, or the user into thinking that an object has terminated and another one has started By exploiting a CRLF injection, an attacker can also insert HTTP headers which could be used to defeat security mechanisms such as a browser’s XSS filter or the same-origin-policy. This allows malicious actors to obtain sensitive information like CSRF tokens. Attackers can also set cookies which could be exploited by logging the victim into the attacker’s account or used to exploit otherwise unexploitable cross-site scripting vulnerabilities."

Impact of the vulnerability

Impact of the vulnerability

The impact of CRLF injections varies depending on the attack context, but will typically cover all the consequences of cross-site scripting and information disclosure that the injection allowed. The technique can also be used to deactivate certain security restrictions like XSS filters and same-origin policy in the victim’s browser, paving the way for other malicious attacks.

The impact of CRLF injections varies depending on the attack context, but will typically cover all the consequences of cross-site scripting and information disclosure that the injection allowed. The technique can also be used to deactivate certain security restrictions like XSS filters and same-origin policy in the victim’s browser, paving the way for other malicious attacks.

How this template works

APIs Selection

The API selection filters in this template are used to extract the query parameter key and value from the request. It uses a regular expression to match any character for the query parameter key and extracts it as "query_key". The query parameter value is extracted as "query_value".

Execute request

The execute section of the template specifies the type of request to be executed, which in this case is a single request. The request is modified using the "modify_query_param" action, where the query_key is replaced with the query_value followed by "%0Aakto-header%3aakto-value". This modification adds a new query parameter "akto-header" with the value "akto-value" to the request.

Validation

The validation section checks the response headers of the executed request. It uses the "for_one" filter to validate that the response contains a header with the key "akto-header" and the value "akto-value". If the validation fails, an error will be raised.

Frequently asked questions

What is CRLF injection in the context of HTTP headers

How can CRLF injection be exploited to defeat security mechanisms

What are the potential impacts of CRLF injections

How can CRLF injections be used to exploit cross-site scripting vulnerabilities

What are some examples of security restrictions that can be deactivated using CRLF injections

How does CRLF injection impact the OWASP Top 10 and HackerOne Top 10 vulnerabilities

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Loved by security teams!

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"We are absolutely thrilled with the testing feature of Akto. We have used it on our graphQL endpoints and it performs flawlessly identifying common API security issues. It's truly a game-changer and we highly recommend Akto to anyone looking to effortlessly secure their API endpoints. With a user-friendly interface, it's the perfect solution for anyone looking to embrace custom rules with context to reduce false positives."

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Security team,

Loom

"We are absolutely thrilled with the testing feature of Akto. We have used it on our graphQL endpoints and it performs flawlessly identifying common API security issues. It's truly a game-changer and we highly recommend Akto to anyone looking to effortlessly secure their API endpoints. With a user-friendly interface, it's the perfect solution for anyone looking to embrace custom rules with context to reduce false positives."

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Loom

"The text editor in Akto is absolutely remarkable. Its user-friendly YAML format strikes the perfect balance between simplicity and power. With intuitive features like 'API selection filter', 'Execute', Validate' creating test rules becomes incredibly easy. Akto's test editor is a game-changer, enabling seamless creation of highly personalized and effective tests that could meet the needs of any modern day organization. "

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Rippling

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