spam as a covert channel

[Justin Mason <jm...@jmason.org>]

A little OT...

This presentation from this year's Black Hat Briefings is really
quite interesting --

  http://www.blackhat.com/presentations/bh-usa-04/bh-us-04-kret.pdf

It really does look like there may be some use of spam, specifically
hashbusters and "chaff" headers, as a covert channel.   However,
the presentation doesn't seem to note that there *is* use of it
for some covert data -- namely the encoded email address of
the recipient, for list-washing....

--j.