Oracle TO_TIMESTAMP_TZ Remote System Buffer Overrun (#NISR16022003b)

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

NGSSoftware Insight Security Research Advisory

Name:    Oracle TO_TIMESTAMP_TZ 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: #NISR16022003b


Description
***********
Oracle's database server contains fuctions for use within queries. The
TO_TIMESTAMP_TZ function exists to convert a string into a timestamp with a
time zone datatype. This function contains an exploitable buffer overflow
vulnerability.

Details
*******
There is a remotely exploitable buffer overflow vulnerability in the
TO_TIMESTAMP_TZ function. A normal statement would look like the following,
converting a character string string to a value of timestamp with time zone:

SELECT TO_TIMESTAMP_TZ('2003-02-016 12:00:00 -8:00','YYYY-MM-DD HH:MI:SS
TZH:TZM') FROM DUAL;

By supplying a long character string for the second parameter an attacker
can overwirte 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 and
Oracle has produced 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