IBM DB2 Universal Database Multiple File Creation Vulnerabilities

iDefense Security Advisory 08.16.07
http://labs.idefense.com/intelligence/vulnerabilities/
Aug 16, 2007

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 following URL.

http://ibm.com/db2/

II. DESCRIPTION

Local exploitation of multiple file creation vulnerabilities in IBM
Corp.'s DB2 Universal Database could allow attackers to elevate
privileges to the superuser.

These vulnerabilities are due to insufficient checking being performed
while handling files with elevated privileges. By setting certain
combinations of environment variables, an attacker is able to create or
append to arbitrary files on the system.

III. ANALYSIS

Exploitation allows local attackers to gain root privileges.

In at least one case, the attacker's umask will be honored when creating
files. In this case, the attacker could create world-writable root-owned
files anywhere on the system. By targeting specific system files, such
as /etc/ld.so.preload or various cron data file locations, an attacker
could execute arbitrary code with superuser privileges.

IV. DETECTION

iDefense confirmed the existence of this vulnerability in version 9.1
Fix Pack 2 of IBM Corp.'s DB2 Universal Database installed on a Linux
system. All prior versions, as well as builds for other UNIX-based
operating systems, are suspected to be vulnerable.

V. WORKAROUND

Setting more strict permissions on the DB2 instance directory can help
mitigate some of these vulnerabilities. Removing the setuid-bit from
all programs included with DB2 can also help mitigate exposure. Note,
these configuration changes have not been thoroughly tested and may
cause adverse behavior.

VI. VENDOR RESPONSE

IBM Corp. has addressed this vulnerability by releasing V9 Fix Pack 3
and version V8 FixPak 15 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: http://www-1.ibm.com/support/docview.wss?uid=swg21255572

VII. CVE INFORMATION

The Common Vulnerabilities and Exposures (CVE) project has assigned the
name CVE-2007-4272 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

03/22/2007  Initial vendor notification
03/23/2007  Initial vendor response
08/16/2007  Coordinated public disclosure

IX. CREDIT

These vulnerabilities were discovered by Joshua J. Drake (iDefense Labs)
and an anonymous researcher.

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X. LEGAL NOTICES

Copyright © 2007 iDefense, Inc.

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