Can you get the flag? Here's the website. We know that the website files live in
/usr/share/nginx/html/and the flag is at
/flag.txtbut the website is filtering absolute file paths. Can you get past the filter to read the flag?
Use a relative path to get up to
/and then access
../../../../flag.txt. We know to go up 4 directories because
/usr/share/nginx/html/is 4 subdirectories from
/. Clicking "Read" displays the flag.