Penetration Testing mailing list archives
Re: [PEN-TEST] Hacking SQL queries ...
From: "Aaron C. Newman" <aaron () NEWMAN-FAMILY COM>
Date: Wed, 7 Feb 2001 19:47:37 -0500
In many SQL databases, two single quotes placed consecutively and embedded as a literal between two other single quotes are translated to a single quote. Basically the first quote is escaping the second quote. For instance: print 'test''test' shows up as test'test Or: print 'test''''test' shows up as test''test Looks like the code is attempting to escape quotes by translating each single quote to two single quotes. The % are simply wildcard values for the search. What can you do with this? It depends. What database platform is being used? How is the connection being made from the web server to the database, ODBC, JDBC, ole db? For instance, if the web server is using jdbc to connect to oracle, a backslash '\' should escape the quote. You can try passing aaa%\' UNION SELECT Password from dba_users WHERE USERNAME = 'SYSTEM which should translate to: SELECT Name FROM Users WHERE Name LIKE 'aaa%\'' UNION SELECT Password from dba_users WHERE USERNAME = 'SYSTEM' Try as many different escape characters as you can think of - &@^\/{}. Try sending a backspace character after the single quote to see if it might erase one of them but not the other, or you may even be able to backspace over the entire statement. Once you've escaped the quote, executing any sql statement becomes easy. HTH, Aaron Newman
-----Original Message----- From: Penetration Testers [mailto:PEN-TEST () SECURITYFOCUS COM]On Behalf Of Aurobindo Sundaram (+1 512 918 1390) Sent: Wednesday, February 07, 2001 3:08 PM To: PEN-TEST () SECURITYFOCUS COM Subject: [PEN-TEST] Hacking SQL queries ... I have to audit a bit of code that does the following SELECT Name FROM Users WHERE Name LIKE '%input%' ORDER BY Name where input is the user-input. When I try the input 'test, the code generated is SELECT Name FROM Users WHERE Name LIKE '%''test%' ORDER BY Name Since I'm an SQL newbie, I'd be curious to know how someone could supply the appropriate input to do bad things on the SQL server - either in R/O or R/W mode If there are SQL hacking pages someplace, a link would be appreciated Thanks, Robin
Current thread:
- Re: [PEN-TEST] Expand right under Win2K Gary Flynn (Feb 06)
- Re: [PEN-TEST] Expand right under Win2K Tamas Foldi (Feb 06)
- <Possible follow-ups>
- Re: [PEN-TEST] Expand right under Win2K Reinder Wiersma (Feb 07)
- [PEN-TEST] Hacking SQL queries ... Aurobindo Sundaram (+1 512 918 1390) (Feb 07)
- Re: [PEN-TEST] Hacking SQL queries ... Nicolas GREGOIRE (Feb 07)
- Re: [PEN-TEST] Hacking SQL queries ... Aaron C. Newman (Feb 07)
- Re: [PEN-TEST] Hacking SQL queries ... Florian Specker (Feb 07)
- Re: [PEN-TEST] Hacking SQL queries ... Philip Wagenaar (Feb 07)
- Re: [PEN-TEST] Hacking SQL queries ... Aaron C. Newman (Feb 10)
- [PEN-TEST] Hacking SQL queries ... Aurobindo Sundaram (+1 512 918 1390) (Feb 07)