Hi Pierre

Of course, because it's BASE64 which means it's encoded in a 64-based system instead of plain text

I'm far from being a pro in interpreting MIME-Headers but the text.zip is just the 'name' of this element, in my opinion, that could be everything. Important is the "Content-Type: application/octet-stream;" which just means that it's a stream of octets - just a stream of code of any possible type, you can see text as a stream of octets aswell (ascii-codes) and when it's 'encoded' in BASE64 you cant read it....
Example: 'Hello Pierre, how are you?' looks like this in BASE64: "SGVsbG8gUGllcnJlLCBob3cgYXJlIHlvdT8="


Matt

Pierre Thomson wrote:

No; the text is unreadable in the raw message.  It only shows in my mail 
reader.  When I tried to include a bit of the encoded ZIP file my message was 
blocked at apache.org... smart guys!

pt


-----Original Message----- From: Matthias Keller [mailto:[EMAIL PROTECTED] Sent: Tuesday, July 27, 2004 11:47 AM To: [EMAIL PROTECTED] Subject: Re: Trying to catch those latest virii....


Hi Pierre

That's interesting but to me it looks like this .zip is just for hiding it, it's not a real zip file (i doubt you could view a real zip file inline... (and I wouldnt like that neither...))

Here's some more dump from my email:
__________

From: "Mail Administrator" <[EMAIL PROTECTED]>
To: xxx
Subject: Returned mail: see transcript for details
Date: Tue, 27 Jul 2004 12:04:59 +0200
MIME-Version: 1.0
Content-Type: multipart/mixed;
        boundary="----=_NextPart_000_0001_F824EC38.FBF36544"
X-Mailer: Microsoft Outlook Express 6.00.2600.0000
X-MIMEOLE: Produced By Microsoft MimeOLE V6.00.2600.0000

This is a multi-part message in MIME format.

------=_NextPart_000_0001_F824EC38.FBF36544
Content-Type: text/plain;
        charset=us-ascii
Content-Transfer-Encoding: 7bit

Dear user of student.ethz.ch,

We have received reports that your email account has been used to send a huge 
amount of junk email during this week.
Obviously, your computer was compromised and now runs a hidden proxy server.

Please follow our instructions in order to keep your computer safe.

Best regards,
student.ethz.ch user support team.


------=_NextPart_000_0001_F824EC38.FBF36544 Content-Type: application/octet-stream; name="document.pif" Content-Transfer-Encoding: base64 Content-Disposition: attachment; filename="document.pif"

wJIqlP/F1Y8......about 20 lines of base64......+qAsLG/

------=_NextPart_000_0001_F824EC38.FBF36544--

_________

Mine actually looks quite normal (mail with attachment) to me... ?

Matt

ps: Yes I know SA isn't here to block my virii but as long as no antivirus company known to me has any signatures for this I need a way to block it... (neither my antivir nor on my laptop my Norton AV 2004 Pro knows this virus...)



Pierre Thomson wrote:



Aha!

I just got one of these myself, and the text is in an inline ZIP file!  I don't 
think any SA rules scan those.

Here's a bit of a raw dump; only the names are changed:

Message-Id: <[EMAIL PROTECTED]>
From: "Mail Delivery Subsystem" <[EMAIL PROTECTED]>
To: [EMAIL PROTECTED]
Subject: Returned mail: see transcript for details
Date: Tue, 27 Jul 2004 10:19:05 -0400
MIME-Version: 1.0
Content-Type: multipart/mixed;
      boundary="----=_NextPart_000_0006_278B1AC0.BB1C5953"
X-Priority: 3
X-MSMail-Priority: Normal
X-Mailer: Microsoft Outlook Express 6.00.2600.0000
X-MIMEOLE: Produced By Microsoft MimeOLE V6.00.2600.0000

This is a multi-part message in MIME format.

------=_NextPart_000_0006_278B1AC0.BB1C5953
Content-Type: text/plain;
      charset=us-ascii
Content-Transfer-Encoding: 7bit


------=_NextPart_000_0006_278B1AC0.BB1C5953 Content-Type: application/octet-stream; name="text.zip" Content-Transfer-Encoding: base64 Content-Disposition: inline; filename="text.zip"

...

and it appears like this:

Dear user of domain.com,

Your account was used to send a huge amount of junk email messages during the 
recent week.
We suspect that your computer was infected by a recent virus and now contains a 
trojaned proxy server.

We recommend you to follow instructions in the attachment in order to keep your 
computer safe.

Have a nice day,
domain.com technical support team.







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