From: cjl <cjl@welchlink.welch.jhu.edu>
Date: Tue, 4 Oct 94 16:59:09 PDT
To: Frederic Halper <fhalper@pilot.njin.net>
Subject: Re: penet remailer
In-Reply-To: <9410042226.AA10893@pilot.njin.net>
Message-ID: <Pine.3.89.9410041953.A17663-0100000@welchlink.welch.jhu.edu>
MIME-Version: 1.0
Content-Type: text/plain



On Tue, 4 Oct 1994, Frederic Halper wrote:

> What's the status of the penet.fi remailer.  Is it secure?
> Reuben
>

I personally don't care for the penet type remailers.  Their only true 
virtue is to allow you to receive return mail to an anon-post.  The 
trade-off is that this is done by a form of identity escrow.  Julf (who 
runs penet.fi) has your e-mail address connected to the anonXXXXX 
identity that you get issued automatically.  As far as reputations go, 
Julf has an excellent reputation in the C-punx community, and there is 
little likelihood of Finnish govt. officials giving in to US Govt. 
pressure to crack down on Julf to turn over his *little black book*.

There was recently an attack on the penet.fi remailer that depended upon 
the ability to spoof the From: lines on messages, some unknown 
person sent hundreds of messages to the anon@penet.fi remailer pretending 
to be hundreds of other people and had those messages sent to alt.test or 
misc.test with some phrase about tunafish in the subject, causing this to 
be known as the *tunafish and spam sandwich attack*.  What this did is 
allocate alot of new anonxxx numbers to people who didn't really want 
them, (also ultimately denying them the secure use of this service, 
because someone knew the anonxxx - TrueName correspondence), for those 
that already had an anonxxx and had set a password things were cool, 
the messages were just rejected.  For those who had an anonxxx and had 
not set the password, this attack revealed the anonxxx corresponding to 
their TrueNames to the person who conducted the attack.  Not a 
particularly secure form of identity escrow for the clueless-at-risk-of- 
identification to be using for posting their wildest homo-erotic fantasies 
to alt.H.E.A.T.fabio.

I was allocated an anxxx I didn't want, and then assigned the password 
in order to deny the attacker any further use of the anxxx with my 
TrueName attached to it.


C. J. Leonard                     (    /      "DNA is groovy"
                                   \ /                - Watson & Crick
<cjl@welchlink.welch.jhu.edu>      / \     <--  major groove
                                  (    \
Finger for public key               \   )
Strong-arm for secret key             /    <--  minor groove
Thumb-screws for pass-phrase        /   )