iDefense Security Advisory 02.08.08
http://labs.idefense.com/intelligence/vulnerabilities/ 
Feb 08, 2008

I. BACKGROUND

Adobe Reader is a program for viewing Portable Document Format (PDF)
documents. Acrobat is the program used to create such documents. More
information is available at the following URLs.

http://www.adobe.com/products/acrobat/ 
http://www.adobe.com/products/reader/ 

II. DESCRIPTION

Remote exploitation of multiple stack-based buffer overflows in
JavaScript methods in Adobe Reader and Acrobat could allow an attacker
to execute arbitrary code as the current user.

These issues exist due to insufficient input validation in several
JavaScript methods. Inadequate checking is performed on the string
length before it is copied into a fixed sized buffer on the stack. If
an attacker supplies a long string, control structures on the stack may
be modified, allowing the execution of arbitrary code.

III. ANALYSIS

Exploitation of these vulnerabilities would allow an attacker to execute
arbitrary code as the current user. In order to exploit these
vulnerabilities, an attacker would have to convince a targeted user to
open a maliciously constructed file. This file could be sent directly
to the targeted user or linked from a website.

IV. DETECTION

iDefense has confirmed these vulnerabilities exist in Adobe Reader 8.1
on Windows XP SP2. It is likely that other Adobe products that handle
PDF files, including previous versions of Adobe Reader, are also
affected.

V. WORKAROUND

Disabling JavaScript in Adobe Reader or Acrobat will limit exposure to
these vulnerabilities. When JavaScript is disabled, Adobe Reader will
prompt the user that some components of the document may not function,
and provide an opportunity to enable it.

VI. VENDOR RESPONSE

Adobe released version 8.1.2 of Adobe Reader and Acrobat to address
these vulnerabilities. Although there is currently no update for
version 7.0.9, Adobe reports it does plan to release one at a later
date. For more information, visit the vendor's advisory at the
following URL.

http://www.adobe.com/support/security/advisories/apsa08-01.html 

VII. CVE INFORMATION

The Common Vulnerabilities and Exposures (CVE) project has assigned the
name CVE-2007-5659 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

10/10/2007  Initial vendor notification
10/10/2007  Initial vendor response
10/26/2007  Request for status
10/26/2007  Status - Est. early January
01/04/2008  Request for status
01/04/2008  Status - Scheduled early February
01/28/2008  Adobe plans patch for 8, but not 7
01/30/2008  Concerns about the plan e-mailed to Adobe
01/31/2008  Telephone call to clarify concerns
02/06/2008  Adobe releases 8.1.2
02/06/2008  Immunity makes PoC available to partners
02/07/2008  Adobe publishes APSA08-01
02/08/2008  Exploit discovered in the wild
02/08/2008  Public disclosure


IX. CREDIT

These vulnerabilities were discovered by Greg MacManus of VeriSign
iDefense Labs.

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X. LEGAL NOTICES

Copyright =A9 2008 iDefense, Inc.

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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
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