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Portswigger/OS Command Injection/Lab1.md

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+# Portswigger OS Command Injection-Lab 
+
+## OS command injection, simple case
+
+This lab is about the Operating System Command Injection , in which if a web application is running a OS script or taking some arguments we can try to include system commands that could compromise ther server.
+
+From the description of the lab it says that command injection vulnerability exists in `product stock checker`.
+
+<img src="https://i.imgur.com/OqcSZtW.png"/>
+
+We can visit and product we want to and then find where that stock checker is.
+
+<img src="https://i.imgur.com/Vi1NxRx.png"/>
+
+If we click the `Check Stock` button , it's going to bring back some results
+
+<img src="https://i.imgur.com/2xe3iJN.png"/>
+
+There's a `POST ` request being sent as we do not see any parameters in URL , so to play around with it let's use `brup suite` to intercept the request
+
+<img src="https://i.imgur.com/H5SWlae.png"/>
+
+Send this request to `Repeater` using `CTRL+R` so we can try sending the request again and again by modifying it.
+
+<img src="https://i.imgur.com/bXUx6yi.png"/>
+
+Here we can see POST request being made to  `/product/stock` and at the bottom we can see the parameters having the value so these parameters are being passed to a shell and then being executed from there are displaying the resutls so there's a chance that there's isn't input sanitzation we can check by adding `;` which is used chain commands to gather 
+
+https://owasp.org/www-community/attacks/Command_Injection
+
+<img src="https://i.imgur.com/dOHe1Te.png"/>
+
+We can do bunch of stuff like reading files on the server and doing other cool stuff but for now our goal was to achieve command injection.
+
+
+<img src="https://i.imgur.com/aoOYLNa.png"/>