One common mistake developers make is using the HTTP GET method to send data that should only be posted using the POST method. This mistake can lead to data manipulation, making your application vulnerable to attacks. Let’s break this down and see why it happens and how to fix it.
The problem arises when GET is used to send data that changes something on the server, like updating user information or deleting records. Since GET requests include data in the URL, this can expose sensitive information and allow bad actors to manipulate data.
This vulnerability occurs because developers may mistakenly use GET requests for actions that should only be handled by POST requests. Here’s why this is dangerous:
With GET, all data is sent as part of the URL, visible to anyone who can see it. This means sensitive data (like user IDs or passwords) can be exposed.
GET requests are often saved in the browser's cache, meaning someone else could access them and potentially misuse the data.
Malicious users can trick other users into clicking on a harmful link, causing unwanted changes on the server without the user’s consent.
Users might accidentally bookmark or share URLs that contain sensitive data in GET requests, exposing it to others.
Always use POST (or PUT/DELETE where needed) for operations that change data on the server. Unlike GET, POST keeps data hidden and safe.
For example, use a form like this for updating user data:Protect your app from malicious requests by using a CSRF token. This unique code makes sure the request is coming from a trusted source.
# Example in FlaskAlways check and clean any data coming from users to prevent harmful input. Use secure libraries that automatically handle this for you.
Use HTTPS (instead of HTTP) to encrypt all communication between the user’s browser and your server, making it harder for hackers to intercept the data.
Regularly check your code to make sure you’re not using GET for actions that change data.