Windows Shell ZIP File Decompression DUNZIP32.DLL Buffer Overflow
Vulnerability

Release Date:
October 12, 2004

Date Reported:
August 2, 2004

Severity:
High (Code Execution)

Vendor:
Microsoft

Systems Affected:
Windows XP (SP1 and earlier)
Windows Me

Overview:
eEye Digital Security has discovered a buffer overflow in DUNZIP32.DLL,
a module that offers support for ZIP compressed folders in the Windows
shell. An exploitable buffer overflow occurs when a user opens a ZIP
folder that contains a long file name.

Technical Details:
This buffer overflow is triggered by an integer overflow. When a ZIP
file containing a long file name (greater than around 0x8000 bytes) is
opened in the Windows shell as a ZIP compressed folder, a stack-based
buffer overflow occurs, allowing an exception handler to be overwritten
and EIP to be hijacked.

Protection:
Retina Network Security Scanner has been updated to identify this
vulnerability.

Vendor Status:
Microsoft has released a patch for this vulnerability. The patch is
available at: 
http://www.microsoft.com/technet/security/bulletin/MS04-034.mspx

Credit:
Discovery: Yuji Ukai

Related Links:
Retina Network Security Scanner - Free 15 Day Trial
http://www.eeye.com/html/Products/Retina/download.html

Greetings:
R.Kanai, Y.Watanabe - Welcome to eEye Japan Team, All Black Hat Japan
2004 attendees, and AV2K4 attendees.

Copyright (c) 1998-2004 eEye Digital Security
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