========================================================================
= WebArchiveX - Unsafe Methods Vulnerability
=
= Vendor Website:
= http://http://www.csystems.co.il/webarchivex/index.aspx
=
= Affected Version:
= WebArchiveX.dll 5.5.0.76 Installed Prior To Sep 6th, 2005
=
= Public disclosure on September 07, 2005
========================================================================
== Overview ==
The WebArchiveX component gives developers the ability to include .MHT
archive creation in their software and is compatible with a wide range
of programming languages.
Prior to September 6th 2005, the activeX component would install and
mark itself 'safe for scripting'. The component offers various methods
that when instantiated by a malicious web site, can be used to read files
from, or write files to the local computer.
== Exploitation ==
The component has an extensive API that can be viewed online;
http://www.csystems.co.il/WebArchiveX/help/api.html
This advisory concentrates on the two following methods;
* MakeArchive - Build MHT web archive (single MHT file)
Boolean MakeArchive(
String htmlFile,
String userAgent,
String mhtFile
);
The MakeArchive method will accept a local path as the mhtFile
parameter, allowing a malicious web site to write a file to the local
drive. By writing to the startup folder, it is possible to create a
.mht that will be executed locally at startup.
* MakeArchiveStr - Build MHT web archive and returns it as a string
String MakeArchiveStr(
String htmlFile,
String userAgent
);
The MakeArchiveStr method will accept a local path as the htmlFile
parameter. After reading in the file, the contents will be returned
to the calling script. This allows a malicious website to read the
contents of any file accessible by the current user.
== Solutions ==
- The vendor has changed the default installation to remove the 'safe for
scripting' entry, but unfortunately has not changed the version number.
The download now includes a readme file that contains;
Why WebArchiveX is not safe for scripting?
------------------------------------------
If WebArchiveX was safe for scripting, then malicious websites
could use WebArchiveX in order to read/write files from/to your
local file system. Please contact support@csystems.co.il for
further details!
In order to make WebArchiveX safe for scripting you can import
the enclosed Registry file WebArchiveX_SafeForScripting.reg.
- To identify if this component is installed on your pc, search the
registry for WebArchiveX entries.
- If the entry is located, remove the 'safe for scripting' entry by
removing these keys;
\Implemented Categories\{7DD95801-9882-11CF-9FA9-00AA006C42C4}
\Implemented Categories\{7DD95802-9882-11CF-9FA9-00AA006C42C4}
- For additional help contact support@csystems.co.il
== Credit ==
Discovered and advised to cSystems August, 2005 by Brett Moore of
Security-Assessment.com
== About Security-Assessment.com ==
Security-Assessment.com is a leader in intrusion testing and security
code review, and leads the world with SA-ISO, online ISO17799 compliance
management solution. Security-Assessment.com is committed to security
research and development, and its team have previously identified a
number of vulnerabilities in public and private software vendors products.
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--
NTBugtraq Editor's Note:
Most viruses these days use spoofed email addresses. As such, using an
Anti-Virus product which automatically notifies the perceived sender of a
message it believes is infected may well cause more harm than good. Someone who
did not actually send you a virus may receive the notification and scramble
their support staff to find an infection which never existed in the first
place. Suggest such notifications be disabled by whomever is responsible for
your AV, or at least that the idea is considered.
--
