CTF Study Notes - Knife&Exec

1. [Geek Challenge 2019] Knife

1. Topic

2. Problem solving steps

At first glance at the code in the title, the prompt is a kitchen knife, so I use the ant sword to connect it.

The connection is successful

. Return to the home directory and find the flag file.

Find the FLAG

3. Summary

1. Learned how to use ant sword and kitchen knife, connect with password
2. eval($_POST["Syc"]);It is a php one-sentence Trojan horse, in which the eval() function executes the content in the function as code, and $_POST can submit files. Therefore, the kitchen knife can be left as a back door.

2. [ACTF2020 Freshman Competition] Exec

1. Topic

2. Problem solving steps

When I did it myself, I had no clue. I didn't expect it to be so simple, and directly access the file...

3. Summary

1. The guess is to ping directly without any filtering, so the input command is executed