I. BACKGROUND
IBM Corp.'s DB2 Universal Database product is a large database server
product commonly used for high-end databases. For more information,
visit the product website at the following URL.
http://ibm.com/db2/
II. DESCRIPTION
Local exploitation of a buffer overflow vulnerability in the db2dasrrm
program, as included with IBM Corp.'s DB2 Universal Database, allows
attackers to elevate privileges to root.
This vulnerability exists due to insufficient validation of the length
of the attacker-supplied "DASPROF" environment variable contents. By
setting the variable to a specially crafted string, an attacker can
cause a buffer overflow when the string is copied into a static-sized
buffer stored on the stack. By overflowing the buffer, the attacker can
overwrite execution control structures stored on the stack and execute
arbitrary code.
III. ANALYSIS
Exploitation allows local attackers to gain root privileges. In order to
exploit this vulnerability, the attacker must have access to execute the
vulnerable set-uid root "db2dasrrm" program.
IV. DETECTION
iDefense has confirmed the existence of this vulnerability in IBM
Corp.'s DB2 Universal Database 9.1 with Fix Pack 4 installed on a Linux
system. Versions for other supported UNIX-like systems should also be
considered vulnerable. All previously released versions are suspected
vulnerable.
V. WORKAROUND
The best defense against this type of vulnerability is to prevent
untrusted users from having code execution abilities on the respective
database server. The following workarounds may also be useful.
Use a more strict permissions setting for the DB2 instance directory would prevent non-instance
users from accessing the set-uid root binaries.
Remove the set-uid bit from all programs included with DB2.
These configuration changes have not been tested and may cause adverse
behavior.
VI. VENDOR RESPONSE
IBM Corp. has addressed this vulnerability with the release of V9.1 Fix
Pack 4a, V8 FixPak 16, and V9.5 Fix Pack 1 of its Universal Database
product. More information can be found at the following URLs.
V8: http://www-1.ibm.com/support/docview.wss?uid=swg21256235
V9.1: http://www-1.ibm.com/support/docview.wss?uid=swg21255572
V9.5: http://www-1.ibm.com/support/docview.wss?uid=swg21287889
VII. CVE INFORMATION
The Common Vulnerabilities and Exposures (CVE) project has assigned the
name CVE-2007-5758 to this issue. This is a candidate for inclusion in
the CVE list (http://cve.mitre.org/), which
standardizes names for
security problems.
VIII. DISCLOSURE TIMELINE
11/29/2007 Initial vendor notification
12/01/2007 Initial vendor response
04/09/2008 Coordinated public disclosure
IX. CREDIT
The discoverer of this vulnerability wishes to remain anonymous.
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X. LEGAL NOTICES
Copyright © 2008 iDefense, Inc.
Permission is granted for the redistribution of this alert electronically. It may not be edited in
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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, this information.
