[ISN] Safe E-Mailing for Dummies

InfoSec News isn at c4i.org
Fri Jan 21 03:07:27 EST 2005


By Michelle Delio
Jan. 20, 2005

Citibank is worried about you.

PayPal is peeved and is about to pull the plug on your account unless
you take action right now. EBay is perturbed about your latest auction
purchase, Visa is fretting that someone may be up to no good with your
credit card, and some bank named SunTrust needs your mother's maiden
name immediately if not sooner.

Plus, at least a dozen of your friends and colleagues have apparently
sent e-mails promising you love, lust, a cool game or access to vital
information if you'll just click on the attached file. Yes, it's just
another happy day in your spam- and scam-packed inbox.

Happily, help is available. Ciphire Mail, a new and
soon-to-be-open-source application, aims to put an end to these sorts
of annoyances with strong and user-friendly e-mail authentication and

E-mail authentication -- confirmation that the stated sender actually
sent the message in question -- could make many e-mail hassles fade
away, since most scams and computer viruses rely on bogus sender
information to lull recipients into a false sense of security.  
Encryption is also a good idea, given the increasing prevalence of
snoopy software.

The Ciphire Mail application, free for individual users, nonprofit
organizations and the press, works in conjunction with all standard
e-mail programs. It operates almost invisibly in the background,
encrypting and decrypting e-mail missives and digitally signing each
message to confirm its source.

Ciphire Labs didn't develop new encryption algorithms or
authentication methods for Ciphire Mail. The idea was just to make the
best existing technology "way easier to use," said Laird Brown, chief
strategist for the Zurich, Switzerland-based company.

In close to a month of testing, Ciphire Mail performed almost
perfectly on computers running Windows XP and Mac OS X version 10.3,
with Outlook 2003, Eudora and the Thunderbird mail clients on the
Windows box, and Eudora and Thunderbird on the Mac.

Setup was a snap: Just download and install the client, choose which
e-mail addresses you want to associate with Ciphire, enter a password,
and the application sets itself up.

Working with the program is just as simple. When two people using the
Ciphire client exchange e-mails, the client intercepts e-mail right
after the Send button is pressed, and before it leaves the computer.  
The recipient's security certificate is retrieved at the Ciphire
Certificate Directory, security checks are performed, and then the
message and any attachments are encrypted with the recipient's key.

Incoming e-mail is also intercepted before it appears in a user's
inbox, the message is decrypted (if necessary) and the sender is
authenticated using the corresponding certificate from the Ciphire
Certificate Directory.

What Ciphire Mail is doing in the background is automatically managing
each user's set of public and private cryptographic keys. The public
key is sent to Ciphire's servers and the private one is stored on the
user's machine. This allows two users to communicate using encryption
without having to exchange private keys, as they must do using other
e-mail encryption programs. No delays in sending or receiving e-mail
were noticeable during testing.

"The difference between Ciphire Mail and other technologies in our
zone is the difference between using and learning how to use," Brown
said. "And none of this has been done at the expense of security. If
anything, we're more secure than the others."

Every Ciphire certificate contains three different 2,048-bit public
keys (RSA, DSA and ElGamal). Ciphire Mail encrypts all e-mails with
two layers. One layer is RSA (with AES) and the other layer is ElGamal
(with Twofish).

If a message is sent to someone who doesn't use Ciphire Mail, the
program simply signs the message, allowing the recipient to confirm
that the message came from the apparent sender.

All of the authentication, encryption and decryption chores were
carried out flawlessly on both test machines. My only problems with
Ciphire Mail were petty aggravations; one would have been avoided if I
had read the manual, and the other issue will be addressed in a future

The primary annoyance was having to enter a password to log into
Ciphire Mail on every reboot of the computer. There's no option to
have the program save the password and automatically login. While this
makes sense from a security standpoint, it's also irritating when you
know your machine is secure and protected from unauthorized physical
or remote access.

Brown said that automatic login is the feature most requested by
Ciphire Mail users, and a "remember my password" feature will be added
to a future version of the program. That's a good thing, as I also
hated waiting the minute or so after booting my computer for Ciphire
to load and request my password. Opening my e-mail client before
Ciphire loaded caused mail transfer errors fixable only by rebooting
the e-mail application.

The only other problem I experienced was sparked by the password-entry
issue. When performing some upgrades on my computer that involved a
lot of rebooting, I uninstalled Cipher Mail to avoid the incessant
requests for my password. I didn't realize I needed to first
deactivate my account before uninstalling the application, and
subsequently received several important encrypted e-mails, sent by
other Ciphire users, that I couldn't read.

Reinstalling the program as per Ciphire's help files and then
forwarding the e-mails to myself didn't help -- I just received
forwarded copies of gibberish. Eventually, I had to request that the
senders send me unencrypted copies of their messages. It was my
mistake -- deactivation is clearly explained in the manual -- but it
would have been helpful if Ciphire also included a message about
deactivating the account in the uninstall routine.

But by and large, Ciphire Mail is flawless, doing what it says it will
do with virtually no effort on the part of its users. So why give all
this wonderfulness away for free? According to Brown, Ciphire Labs
wants to "share the wealth" that it hopes will soon be generated by
the commercial version of Ciphire Mail for enterprises, expected to be
released in spring 2005.

Ciphire Labs also intends to release the source code to Cipher Mail
within the year, after the application is out of beta and the code is
deemed stable.

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