NSOADV-2010-003: DATEV ActiveX Control remote command execution

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Title: DATEV DVBSExeCall ActiveX Control remote
command execution
Severity: Critical
Advisory ID: NSOADV-2010-003
CVE Number: CVE-2010-0689
Found Date: 11.01.2010
Date Reported: 28.01.2010
Release Date: 25.02.2010
Author: Nikolas Sotiriu
Mail: nso-research at sotiriu.de
Website: http://sotiriu.de/
Twitter: http://twitter.com/nsoresearch
Advisory-URL: http://sotiriu.de/adv/NSOADV-2010-003.txt
Vendor: DATEV (http://www.datev.de/)
Affected Products: DATEV Base System (Grundpaket Basis)
Affected Component: DVBSExeCall Control ActiveX Control V.1.0.0.1
Remote Exploitable: Yes
Local Exploitable: No
Patch Status: Vendor released a patch (See Solution)
Discovered by: Nikolas Sotiriu
Disclosure Policy: http://sotiriu.de/policy.html
Thanks to: Thierry Zoller: For the permission to use his
Policy

Background:

DATEV eG is a German Company, which makes Software for tax advisors and
lawyers.

The affected Base System has to be installed on all systems that
need DATEV Software.

Description:

During the installation of the DATEV Base System (Grundpaket Basis) an
ActiveX Control will be installed (DVBSExeCall.ocx), in which the
function "ExecuteExe" is vulnerable to a command execution bug.

Name: ActiveX-Control zum Öffnen von LEXinform und der InfoDB
Vendor: DATEV eG
Type: ActiveX-Steuerelement
Version: 1.0.0.1
GUID: {C1CF8B56-3147-41A2-B9BF-79437EED7AFC}
File: DVBSExeCall.ocx
Folder: C:\DATEV\PROGRAMM\HLPDVBS\
Safe for Script: True
Safe for Init: True
IObjectSafety: False

NOTE: The affected ActiveX Control will be installed by any DATEV
Software, so each system with a DATEV installation is vulnerable.

Proof of Concept :

Weaponized PoC demonstration video:
±---------------------------------
http://sotiriu.de/demos/videos/nso-2010-003.html

Solution:

DATEV Advisory
±------------
http://www.datev.de/info-db/1080162 (German)

Service-Release Paket V. 1.0
±--------------------------
http://www.datev.de/portal/ShowPage.do?pid=dpi&nid=96550

Disclosure Timeline (YYYY/MM/DD):

2010.01.11: Vulnerability found
2010.01.25: Initial contact per Online forms
2010.01.26: Initial vendor response
2010.01.26: Ask for a PGP Key and send the Disclosure Policy to vendor.
[-] No Response
2010.01.28: Ask if vendor received my last email.
2010.01.28: Vendor is unable to use PGP.
2010.01.28: Sent PoC, Advisory, Disclosure policy and planned disclosure
date (2010.02.11) to Vendor
2010.01.29: Vendor acknowledges the reception of the advisory and start
to develop a patch.
2010.02.02: Patch is finished. Vendor wishes to delay the release to the
2010.02.25.
2010.02.02: Changed release date to 2010.02.25.
2010.02.03: Patch is published
2010.02.25: Release of this Advisory