SSTI in Flask and Jinja

Fuzzing vulnerable payloads in request body and query params to assess Server-Side Template Injection vulnerability.

Server Side Template Injection (SSTI)

Impact of the vulnerability

Successful exploitation might compromise sensitive AWS information which attacker can use to get unauthorized access to AWS.

How this template works

APIs Selection

The template uses regular expressions to match any request payload or query parameter key. It extracts the matched key and assigns it to the variables "payloadKey" and "queryKey" respectively.

Execute request

The template modifies the query parameter "queryKey" by injecting the value "%24%7B%277%27%20*%207%7D", which represents the expression "${'7'*7}". It also modifies the request body parameter "payloadKey" by injecting the value "${'7'*7}". These modifications aim to test for Server-Side Template Injection vulnerabilities.

Validation

The template validates the response payload by checking if it contains the string "7777777". If the response payload contains this string, it indicates a successful exploitation of the Server-Side Template Injection vulnerability.

Frequently asked questions

What is Server-Side Template Injection (SSTI) and how does it relate to Flask and Jinja templates

How does the SSTI in Flask and Jinja test identify and exploit vulnerabilities

What is the impact of a successful exploitation of the SSTI vulnerability in Flask and Jinja

What are the severity and category of this test

What are the tags associated with this test

Are there any references or resources available for further information on SSTI in Flask and Jinja

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