From the page source, we can no longer use “;”, “|” and “&” but we are still using similar attack from previous level. We need to utilize grep to match anything from the password file so that we can see the password for the next level. To match any character, we can use “.” character in grep with the file path plus the # sign to ignore anything afterward.
. /etc/natas_webpass/natas11 #
will give us the next password.
Here are some references to grep.