Oracle Database Server is a family of database products that range from
personal databases to enterprise solutions. Further information is
Remote exploitation of an access validation vulnerability in multiple
versions of Oracle Corp.'s Oracle Database Server could allow
authenticated users to obtain administrative privileges.
The problem specifically exists because although Oracle 9i Databases
have the account ctxsys locked by default, ctxsys.driload is still
accessible by users. The package ctxsys.driload allows every user to
execute commands as DBA. A database connection with execute permissions
on the package ctxsys.driload is required. The following example query
executed under the credentials of the default user scott (password
'tiger') demonstrates this vulnerability:
SQL> exec ctxsys.driload.validate_stmt
('create user hacker identified by hacker');
SQL> exec ctxsys.driload.validate_stmt('grant dba, connect to hacker');
Successful exploitation allows authenticated users to execute arbitrary
commands as DBA, which allows complete control over the database.This
vulnerability is the result of three separate issues:
1. Some packages of ctxsys are granted to public (e.g. driload)
2. The package driload uses the permissions of the owner (CTXSYS = DBA)
instead of the caller of the procedure (e.g. scott).
3. The package driload executes every valid SQL command (e.g. create
user, grant dba to, drop user, etc.) without further tests.
Locking of the ctxsys user account does not prevent exploitation.
DEFENSE has confirmed that Oracle Database Server version 188.8.131.52 is
vulnerable. It has been reported that 184.108.40.206, and 220.127.116.11 are
vulnerable. It is suspected that all versions earlier than 18.104.22.168 are
If ctxsys is not needed, drop the user by executing the following SQL
SQL> Drop user ctxsys
Otherwise, revoke public privileges to the vulnerable object via the
following SQL statement:
SQL> revoke grant ctxsys.driload from public
"[This] issue [has] been addressed in Alert 68."
The Common Vulnerabilities and Exposures (CVE) project has assigned the
name CAN-2004-0637 to this issue. This is a candidate for inclusion in
the CVE list (http://cve.mitre.org), which standardizes names for
05/06/2004 Initial vendor notification
05/06/2004 iDEFENSE clients notified
05/06/2004 Initial vendor response
09/02/2004 Public disclosure
Alexander Kornbrust (www.red-database-security.com) is credited with
Get paid for vulnerability research
Copyright © 2004 Verisign, Inc.
Permission is granted for the redistribution of this alert
electronically. It may not be edited in any way without the express
written consent of iDEFENSE. If you wish to reprint the whole or any
part of this alert in any other medium other than electronically, please
email firstname.lastname@example.org for permission.
Disclaimer: The information in the advisory is believed to be accurate
at the time of publishing based on currently available information. Use
of the information constitutes acceptance for use in an AS IS condition.
There are no warranties with regard to this information. Neither the
author nor the publisher accepts any liability for any direct, indirect,
or consequential loss or damage arising from use of, or reliance on,