<<< Date Index >>>     <<< Thread Index >>>

dtSearch DUNZIP32.dll Buffer Overflow Vulnerability



Networksecurity.fi Security Advisory (21-12-2005)

Title: dtSearch DUNZIP32.dll Buffer Overflow Vulnerability
Criticality: High (3/3)
Affected software: dtSearch versions prior than 7.20 Build 7136
Author: Juha-Matti Laurio
Date: 21th December, 2005
Advisory ID: Networksecurity.fi Security Advisory (21-12-2005) (#15)
CVE reference: CVE-2004-1094

- From the vendor:
"Instantly Search Terabytes of Text
The dtSearch product line can instantly search terabytes of text across a desktop, network, Internet or Intranet site."

- Description:
dtSearch document search system is confirmed as affected to remote type buffer overflow vulnerability. The vulnerability is caused due to a boundary error in a 3rd-party compression library's (DUNZIP32.dll) remarkable old, vulnerable version used when handling packed .ZIP documents. InnerMedia DynaZip compression library mentioned is responsible for indexing and displaying operations. This can be exploited to cause a buffer overflow via a specially crafted zipped document. When a specially crafted .zip document containing a file with an overly long filename (a file name or files inside a ZIP) is opened, the application will crash and the attacker may be able to execute arbitrary code on user's system (see US-CERT VU#582498 reference).

- Detailed description:
Affected DynaZip library examined is version from December, 2002, file version 5.0.0.2. According to InnerMedia company versions 5.00.03 and prior are affected. The following remarkable old file was copied to C:\Program Files\dtSearch\bin directory during an installation process when tested:
File name: dunzip32.dll
Date stamp: 6th December, 2002 04:05PM
File version: 5.0.0.2
Description: DynaZIP-32 Multi-Threading UnZIP DLL

NOTE: Dunzip32.dll is being installed into the same directory as the application executable of dtSearch Engine if dtSearch has been installed on end-users' machines. If the situation is as described, updating of the libary on end-users' machines by applying a software update is also needed.

From US-CERT VU#582498:
"Impact:
If a remote attacker can persuade a user to access a specially crafted zip file, the attacker may be able to execute arbitrary code on that user's system possibly with elevated privileges."

- Affected versions:
The vulnerability has been confirmed in dtSearch Desktop with Spider version 7.10 (Build 7045). Other versions may also be affected.
The newest dtSearch version from 6.x product line is dtSearch 6.5 Build 6608.
All earlier versions (vendor's Web pages list versions 1.x to 5.25) are probably affected as well.

- OS:
Microsoft Windows (Win 95/98/ME/NT/2000/XP/2003/.NET)
Tests was done with Microsoft Windows XP Professional SP2 and Microsoft Windows 2000 Professional SP4 fully patched.

- Solution status:
Vendor has issued a patch shipped with immune library version 5.00.07. It can be obtained by downloading a patch from:
http://www.dtsearch.com/download.html#upgrades

- Software:
dtSearch 7.x
dtSearch 6.x
http://www.dtsearch.com/PLF_desktop.html (Desktop with Spider)

Vendor and vendor Home Page:
dtSearch Corp.
http://www.dtsearch.com

Vendor product Web page:
http://www.dtsearch.com/PLF_desktop.html (Desktop with Spider)

- Solution:
Apply a patch 7.20 Build 7136 (version number 7.20.7136.1):
http://www.dtsearch.com/download.html#upgrades

- CVE information:
The Common Vulnerabilities and Exposures (CVE) project has assigned the name CVE-2004-1094 on 20th December, 2005 to this issue. This is a candidate for inclusion in the CVE list (http://cve.mitre.org ), which standardizes names for security problems.
http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2004-1094
The CVSS (Common Vulnerability Scoring System) severity level metric of issue CVE-2004-1094: 10 (High)

- References:
US-CERT VU#582498:
"InnerMedia DynaZip library vulnerable to buffer overflow via long file names"
http://www.kb.cert.org/vuls/id/582498
From the vulnerability note:
"Users are encouraged to contact their software vendors if they suspect they are vulnerable."
Upgrade information for version 6.x or earlier:
http://support.dtsearch.com/faq/dts0201.htm

Credit information:
This vulnerability was researched by Juha-Matti Laurio, Networksecurity.fi (Finland).

Timeline:
12-Oct-2005 - Vulnerability researched and confirmed
05-Nov-2005 - Vendor was contacted
05-Nov-2005 - Vendor's reply, vendor informed about upcoming, fixed version and timeline
06-Nov-2005 - Vendor issues a patch, detailed research
20-Dec-2005 - CVE information submission sent to Mitre.org
20-Dec-2005 - Mitre.org assigns CVE-2004-1094
21-Dec-2005 - Security companies and several CERT units contacted
23-Dec-2005 - Public disclosure

A full version of security advisory is located at http://www.networksecurity.fi/advisories/dtsearch.html

Networksecurity.fi Weblog (Finnish language): http://networksecurity.typepad.com/