Validating user input in php the dating game board game vintage
Also, doing various things like checking Content-type and checking for a well-formed image can prove very valuable as well.
Some people take an entirely different approach to protecting their applications, and it's what some refer to as "data massaging." Data massaging is the process of sanitizing data before using it, despite the presence of suspicious data.
Surprisingly, it’s rather difficult to handle file uploads in a secure manner, and most of today’s developers generally don't seemingly have the understanding needed to do so.
Some of the ways that people generally try to protect against this pervasive issue are to: 1) Filter uploads based on file extensions 2) Check the Content-type header of uploaded files 3) Ensure that the file is a valid example of the expected file type All of these help, but by themselves each approach still has issues that need addressing.
We can send a Content-type header of "lol/wut" if we like, or "ilovemydoggy/heissocute" or even "hacknaked/bowtomyfirewallahh".
It simply doesn't matter, and as such we can very easily satisfy the application with a Content-type header of "image/gif" despite the fact that we, as pen testers, are likely uploading a file using a "php" extension.
Perhaps you're saying to yourself at this point: "Self, it seems it's not effective to check things like file extensions and user-provided data.
What I need to do is to check the content of the file itself!
It protects against My SQL injection and URL exploitations. I should have named it sanitizer to differentiate what I meant.Doing this sort of filtering on the server-side has issues too, though.Here's a PHP script which takes a file upload and checks the file extension against a list of "bad" file extensions: That’s a nice try, but it won't work on Web sites where the server is set to execute any file other than those with the standard PHP file extensions.Starting with the what and why of Code Igniter, Jon introduces key concepts such as the MVC pattern and libraries by demonstrating how to create static pages, then storing and displaying magazine info in a database.Advanced topics like classes and helpers are explored to validate user input, upload files, and much more.