SPIDynamics WebInspect Cross-Application Scripting (XAS)
Dear bugTraq,
Cross application scripting attacks (data obtained from untrusted
source is sent unfiltered from trusted application to browser) in
different applications are reported by anonymous author.
In Russian version of article "XSS - WEB = Cross-Applications
Scripting" (signed (c)oded by QQLan@xxxxxxxxx)
http://www.security.nnov.ru/articles/xas/
there are remote cross-application scripting attack in SPIDynamics
WebInspect and domain level cross-application attack with potential
privilege escalation for user with limited delegated control under OU
to domain administrator account is also described for Windows domain
group policy editor (gpedit.msc) under Windows XP and Windows Server
2003.
Below is original anonymous report for cross application scripting in
SPIDynamics WebInspect
(http://www.security.nnov.ru/Fnews30.html)
SPIDynamics WebInspect Cross-Application Scripting (XAS)
I. BACKGROUND
SPIDynamics WebInspect is powerful security assessment tool for Web application
vulnerable to XAS which
could lead to remote code execution.
II. DESCRIPTION
As many applications WebInspect uses external programs and Windows components
for different purposes.
It is very common to use COM object of Internet Explorer for render reports and
displays data. WebInspect
in not an exception.
When reports is generated, some parts of scanned site (for example URLs) are
included into HTML file
(file://C:\Program Files\SPIDynamics\WebInspect\Working\vulnerability.htm),
which opens in IE.
Because WebInspect doesn't properly normalize displayed data, part of URL or
other data can be parsed by IE
as DHTML, for example JavaScript, and leads to code execution on the computer
where scanner is installed.
III. ANALYSIS
Successful exploitation allows remote attackers to execute arbitrary script
code on the host, where
scanner is installed with privileges of user who launch the scanner. Victim
should scan site and open
report.
Typically scanner runs on administrator's or security auditor's box with a lot
of interesting data.
It possibly runs under high-privileged account.
Attacker should create specially crafted site with vulnerability to be
displayed in report.
"Vulnerable" URL should include script code. Example of such report is a
"Hidden Form Value Vulnerability
ID: 4727".
By default script is executed in Internet Security Zone of IE (not sure). But
with little effort attacker
can use predictable resource location to bypass restrictions of Internet Zone
and execute script in "My
Computer" security zone.
Example:
<script>window.open('file://C:\\Program
Files\\SPIDynamics\\WebInspect\\Working\\vulnerability.htm')</script>
Attacker can use social engineering to install full featured application, for
example new version of
"SPIDynamics Reported ActiveX".
IV. DETECTION/POC
Following asp file can be used to reproduce vulnerability:
<*****************iisstart.asp***********************>
<HTML><HEAD><BODY>
<%
if request.querystring<>"" then
response.write request.querystring
end if
%>
<form action="script>/<script>window.open(%27file://C:\\Program
Files\\SPIDynamics\\WebInspect\\Working\\vulnerability.htm%27)</script>"
method=get> Please login:<br>
<input type=submit value="Login"><br> <input type=hidden name='hidden'
value="Login"><br> </form>
</BODY></HTML>
</*****************iisstart.asp***********************>
You should change default error page to iisstart.asp (see screenshot in
attach). Scan results can be found
in attached files.
V. VENDOR RESPONSE
Initial vendor response received
VII. DISCLOSURE TIMELINE
04/15/2005 Initial vendor notification
04/15/2005 Initial vendor response
VIII. WORKAROUND
Disable Active Scripting in My Computer Zone
(http://support.microsoft.com/default.aspx?scid=kb;en;833633)
IX. LEGAL NOTICES
This advisory is being provided to you under the RFPolicy documented at
http://www.wiretrip.net/rfp/policy.html. You are encouraged to read this
policy; however, in the interim,
you have approximately 5 days to respond to this initial email.
Thanks: 3APA3A for spellcheck & malware.com for some ideas.