Oracle TZ_OFFSET Remote System Buffer Overrun (#NISR16022003c)

["NGSSoftware Insight Security Research" <nisr () nextgenss com>]

NGSSoftware Insight Security Research Advisory

Name:    Oracle TZ_OFFSET Remote System Buffer Overrun
Systems Affected:  All platforms; Oracle9i Database Release 2, 9i Release 1,
8i, 8.1.7, 8.0.6
Severity:  High Risk
Category:               Remote System Buffer Overrun
Vendor URL:   http://www.oracle.com
Author:   Mark Litchfield (mark () ngssoftware com)
Date:   16th February 2003
Advisory number: #NISR16022003c

Description
***********
Oracle's database server contains fuctions for use within queries. The
TZ_OFFSET function returns the time zone offset corresponding to the value
entered based on the date the statement was executed. For example:

SELECT TZ_OFFSET('US/Eastern') FROM DUAL;

would return the time zone offset value of -04:00. The TZ_OFFSET() function
contains a remotely exploitable buffer overflow vulnerability.


Details
*******
There exists a remotely exploitable buffer overflow vulnerability in the
TZ_OFFSET function. By supplying a long character string for the time zone
name an attacker can overwrite a saved return address on the stack of Oracle
process.  Before this issue can be exploited an attacker must be able to log
on to the database server with a valid user ID and password, but as the
TO_TIMESTAMP_TZ() function can be executed by PUBLIC by default any user of
the system can gain control. Any arbitrary code supplied by an attacker
would execute with the same privileges as the user running the service; this
account is typically "Oracle" on linux/unix based platforms and Local System
on Windows based operating systems such as NT/2000/XP. As such this allows
for a complete compromise of the data stored in the database and possibly a
complete compromise of the operating system.


Fix Information
***************
NGSSoftware alerted Oracle to this vulnerability on 30th September 2002.
Oracle has developed a patch which is available from

http://otn.oracle.com/deploy/security/pdf/2003alert50.pdf

A check for these issues has been added to NGSSQuirreL for Oracle, a
comprehensive automated vulnerability assessment tool for Oracle Database
Servers of which more information is available from the NGSSite

http://www.ngssoftware.com/software/squirrelfororacle.html

Further Information
*******************
For further information about the scope and effects of buffer overflows,
please see

http://www.ngssoftware.com/papers/non-stack-bo-windows.pdf
http://www.ngssoftware.com/papers/ntbufferoverflow.html
http://www.ngssoftware.com/papers/bufferoverflowpaper.rtf
http://www.ngssoftware.com/papers/unicodebo.pdf


About NGSSoftware
*****************
NGSSoftware design, research and develop intelligent, advanced application
security assessment scanners. Based in the United Kingdom, NGSSoftware have
offices in the South of London and the East Coast of Scotland. NGSSoftware's
sister company NGSConsulting, offers best of breed security consulting
services, specialising in application, host and network security
assessments.

http://www.ngssoftware.com/
http://www.ngsconsulting.com/

Telephone +44 208 401 0070
Fax +44 208 401 0076

enquiries () ngssoftware com