The following security advisory is sent to the securiteam mailing list, and can
be found at the SecuriTeam web site: http://www.securiteam.com
- - promotion
The SecuriTeam alerts list - Free, Accurate, Independent.
Get your security news from a reliable source.
http://www.securiteam.com/mailinglist.html
- - - - - - - - -
Multiple Vendor libchm Page Block Length Memory Corruption Vulnerability
------------------------------------------------------------------------
SUMMARY
<http://www.jedrea.com/chmlib/> CHMlib is "an open source library used to
read Microsoft CHM, compressed HTML, files. CHM files were originally
designed for use by Microsoft as help files, but are now commonly used to
store e-books. The 'xchm' program uses CHMlib to display CHM files".
Successful exploitation of this vulnerability allows an attacker to
execute arbitrary code with the permissions of the user viewing the file.
An attacker would have to first convince the user to view the CHM file
through some type of social engineering.
DETAILS
Vulnerable Systems:
* CHMlib version 0.38
Immune Systems:
* CHMlib version 0.39
CHM files contain various tables and objects stored in "pages." When
parsing a page of objects, CHMlib passes an unsanitized value from the
file to the alloca() function. This allows an attacker to shift the stack
pointer to point to arbitrary locations in memory. Consequently it is
possible to write arbitrary data from the file to arbitrary memory
locations.
Vendor Status:
The CHMlib maintainer has addressed this issue in version 0.39.
Disclosure Timeline:
* 01-24-07 - Initial vendor notification
* 01-24-07 - Initial vendor response
* 01-26-07 - Coordinated public disclosure
ADDITIONAL INFORMATION
The information has been provided by iDefense.
The original article can be found at:
<http://labs.idefense.com/intelligence/vulnerabilities/display.php?id=468>
http://labs.idefense.com/intelligence/vulnerabilities/display.php?id=468
========================================
This bulletin is sent to members of the SecuriTeam mailing list.
To unsubscribe from the list, send mail with an empty subject line and body to:
list-unsubscribe@securiteam.com
In order to subscribe to the mailing list, simply forward this email to:
list-subscribe@securiteam.com
====================
====================
DISCLAIMER:
The information in this bulletin is provided "AS IS" without warranty of any
kind.
In no event shall we be liable for any damages whatsoever including direct,
indirect, incidental, consequential, loss of business profits or special
damages.
