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Microsoft Windows XP SP2 Firewall issue


From: edubp2002 () hotmail com
Date: 24 Mar 2006 10:34:46 -0000

Windows XP firewall had improvements after SP2 and it display alerts about programs trying to listen on a port (acting 
as a 'server') to the users. It doesnt display the path for the file nor the last extension, instead, it only displays 
its description or name without the final extension. 

if u place a trojan with 'no name' in some dir, windows firewall will mistakenly alert about a 'folder name\', this can 
be misused to trick people into giving access to a malicious application thinking it is a legitim one. example below 
will make people think Internet Explorer is asking for access, when actually,it is not! :

==============example============================
in a cmd prompt:
copy mytrojan.exe "\program files\Internet Explorer\.exe" 
cd \program files\internet explorer
start .exe 
=================================================
An alert will show up saying 'Internet Explorer\' has been blocked and will ask if you want unblock it when it should 
alert about '.exe'.This could trick most people into thinking the firewall alerted about a well known legitim 
application.

another issue with the firewall is using NTFS alternate data streams. if u execute a file that is 'forked' to another 
one, no alerts will show up, not at all, but I dont think this is a security issue since on the computers I tested I 
wasnt able to direct connect.
example:

===============================================
in a cmd prompt:
type c:\mytrojan c:\windows\notepad.exe:mytrojan.exe
start c:\windows\notepad.exe:mytrojan.exe
===============================================
no alerts ;)

ps: every exploit code or details about a vulnerability here in Securityfocus are not found.
when you click in the exploit menu of any vulnerability and there is some kind of exploit code attached it will return 
an error such as 'the document you are looking for cannot be found' ... just like a broken link. and this issue is 
happening for some weeks. is this an error ?... waiting feedback on this issue.
cheers,
Edu










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