-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

iDefense Security Advisory 03.25.09
http://labs.idefense.com/intelligence/vulnerabilities/ 
Mar 25, 2009

I. BACKGROUND

The Sun Java JRE is Sun's implementation of the Java runtime. For more
information, see the vendor's site found at the following link.

http://www.java.com 

II. DESCRIPTION

Remote exploitation of a heap corruption vulnerability in Sun
Microsystems Inc.'s Java JRE could allow an attacker to execute
arbitrary code with the privileges of the current user.

Values from the GIF file are used to calculate an offset to store data
in a dynamic heap buffer. These values are not validated before use,
which allows an attacker to store controlled data outside of the bounds
of the allocated buffer. This leads to corruption of object pointers,
which can be leveraged to execute arbitrary code.

III. ANALYSIS

Exploitation of this vulnerability results in the execution of arbitrary
code with the privileges of the user viewing the web page. To exploit
this vulnerability, a targeted user must load a malicious webpage
created by an attacker. An attacker typically accomplishes this via
social engineering or injecting content into compromised, trusted
sites. After the user visits the malicious web page, no further user
interaction is needed.

Since the attacker has the ability to use Java code to carefully sculpt
the layout of the heap, this vulnerability can be reliably exploited.

IV. DETECTION

iDefense has confirmed the existence of this vulnerability in Java JRE
version 1.6_11. Previous versions may also be affected.

Sun Microsystems reports that the vulnerability can occur in the
following Java SE and Java SE for Business releases for Windows,
Solaris, and Linux:

    * JDK and JRE 6 Update 12 and earlier

Note: JDK and JRE 5.0, SDK and JRE 1.4.2 and 1.3.1 are not affected.

V. WORKAROUND

iDefense is currently unaware of any workarounds for this issue. The
vulnerability occurs in a core library used by JRE, so it is not
possible to disable the code.

VI. VENDOR RESPONSE

Sun Microsystem Inc. has released a patch which addresses this issue.
For more information, consult their advisory at the following URL:

http://sunsolve.sun.com/search/document.do?assetkey=1-66-254571-1 

VII. CVE INFORMATION

A Mitre Corp. Common Vulnerabilities and Exposures (CVE) number has not
been assigned yet.

VIII. DISCLOSURE TIMELINE

02/18/2009  - Initial Contact
02/18/2009  - PoC Requested
02/19/2009  - PoC Sent
03/10/2009  - Disclosure Date Set
03/25/2009  - Coordinated Public Disclosure

IX. CREDIT

This vulnerability was reported to iDefense by regenrecht.

Get paid for vulnerability research
http://labs.idefense.com/methodology/vulnerability/vcp.php 

Free tools, research and upcoming events
http://labs.idefense.com/ 

X. LEGAL NOTICES

Copyright =A9 2009 iDefense, 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 e-mail customerservice@idefense.com 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, this information.
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.7 (MingW32)
Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org 

iD8DBQFJy+P3bjs6HoxIfBkRArfOAKD8gA5zAQfOaRqVYa1UsDoWq2fg7gCgsPga
m+Dewp2k5Tgfh1mIdU6Dn7w=G8tg
-----END PGP SIGNATURE-----