Microsoft Internet Explorer 5 Favicon Buffer Overflow Vulnerability

Bugtraq ID:	172
Class:	Boundary Condition Error
CVE:
Remote:	Yes
Local:	No
Published:	May 03 1999 12:00AM
Updated:	May 03 1999 12:00AM
Credit:	This vulnerability was discovered by Flavio Veloso <[email protected]> and published in the Bugtraq mailing list.
Vulnerable:	Microsoft Internet Explorer 5.0 for Windows 98 + Microsoft Windows 98 + Microsoft Windows 98 Microsoft Internet Explorer 5.0 for Windows 95 + Microsoft Windows 95 + Microsoft Windows 95
Not Vulnerable:	Microsoft Internet Explorer 5.0 for Windows NT 4 + Microsoft Windows NT 4.0 + Microsoft Windows NT 4.0

Microsoft Internet Explorer 5 Favicon Buffer Overflow Vulnerability

A vulnerability in Internet Explorer 5's processing of the icon used in the "Favorites" menu may allow malicious web sites to execute arbitrary code in the users machine.

A new feature of Internet Explorer 5.0 allows web site operators to custumize the display of their bookmark entry with an icon when it is displayed in the "Favorites" menu. When the user bookmarks a page IE will request the file "favicon.ico" from the web site. This feature is only available in Win32 platforms using a Win32 icon format.

A malformed icon can cause a stack buffer oveflow in IE 5.0. The GPF is triggered in the USER.EXE module.

Microsoft Internet Explorer 5 Favicon Buffer Overflow Vulnerability

Currently the SecurityFocus staff are not aware of any exploits for this issue. If you feel we are in error or are aware of more recent information, please mail us at: [email protected].

Microsoft Internet Explorer 5 Favicon Buffer Overflow Vulnerability

Solution:
Apply the Microsoft patch available at:

http://www.microsoft.com/windows/ie/security/favorites.asp

Microsoft Internet Explorer 5 Favicon Buffer Overflow Vulnerability

References:

• MSIE 5 favicon bug (Flavio Veloso )
  
• Q231450: Update Available for the "Malformed Favorites Icon" Issue in Internet E (Microsoft)