Testing for Insecure Direct Object Reference (IDOR)

Allowing unauthorized direct access to files or resources on a system based on user-supplied input is known as Insecure Direct Object Reference (IDOR). This vulnerability allows the bypassing of authorization checks placed on such files or resources. IDOR is a result of unchecked user supplied input to retrieve an object without performing authorization checks in the application code.

Getting ready

Using OWASP Mutillidae II as our target application, let's manipulate the value of the phpfile parameter to determine whether we can make a call to a direct object reference on the system, such as /etc/passwd file.

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