Re: HTML email "bug", of sorts.

["John D. Hardin" <jhardin () impsec org>]

On Sat, 18 Aug 2001, Alex Prestin wrote:

> <DEFANGED_IMG
> src="http://www.megahardcoresex.com/sites/XXXXXXXX0 (continued)
> 3b/sf03b08152001.gif?M=XXXXXXXXX&ID=wakko () bitey net" width="1" height="1"> 
>
> See it?  A web bug.  If I opened this mail in an HTML-capable
> browser, that little image would've popped up and I would've been
> none the wiser.  My address would also have been verified by the
> sender, and stored in a large database of valid recipients.

This is well-known. BGSOUND tags are also vulnerable to misuse in this
manner.

> So, anyone have any idea of how to deal with this latest little
> spammer toy?  Is there any effective way to filter out web bugs
> without adversely affecting the delivery intact of legitimate
> messages?

http://www.impsec.org/email-tools/procmail-security.html

(If you're running a procmail-capable mail server.)

Looking at the tag above shows you what it does...

--
 John Hardin KA7OHZ   ICQ#15735746   http://www.wolfenet.com/~jhardin/
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