The RISKS Digest
Volume 16 Issue 34

Wednesday, 24th August 1994

Forum on Risks to the Public in Computers and Related Systems

ACM Committee on Computers and Public Policy, Peter G. Neumann, moderator

Please try the URL privacy information feature enabled by clicking the flashlight icon above. This will reveal two icons after each link the body of the digest. The shield takes you to a breakdown of Terms of Service for the site - however only a small number of sites are covered at the moment. The flashlight take you to an analysis of the various trackers etc. that the linked site delivers. Please let the website maintainer know if you find this useful or not. As a RISKS reader, you will probably not be surprised by what is revealed…


Bug in Microsoft Word
Chris Norloff
Report on the 1993 Gatwick near-miss
Peter Ladkin
The new Cray and Unix passwords...
Peter Wayner
Most home security alarms are false
Mich Kabay
Misconceptions about PGP 2.6 from MIT
Philip Zimmermann
"Secrets of a Super Hacker" by Fiery
Rob Slade
International Cryptography Institute
Dorothy Denning
Info on RISKS (comp.risks)

Bug in Microsoft Word

Wed Aug 24 14:55:07 1994
There's a bug in Microsoft Word 6.0 and 6.0a: what you see is not what you
get.  I saw this in _Windows Magazine_, May 1994 (Fred Langa's column
"Win.INI", pages 11 and 14).  I checked the problem with a copy of Word 6.0a,
and confirmed it exists.  I'm surprised I haven't seen it in RISKS, and
checked the archive, but could find no mention of it in volumes 15 or 16.


Word has a summary info area, for each document, that cannot be turned off.
If you do not enter information in the summary (which is the default setting)
then Word will lift sentences out of the beginning of your document and place
them in the summary, without telling you.  Even if you then change the summary
info, the lifted sentences may still remain hidden in the document, visible to
any text editor (but not visible in Word).

If all you use is printed copies, you're okay.  However, if you give somebody
the file on disk or send it by email, then there may be unintended information
in the file — not great for people working with sensitive, competition
sensitive, or classified information.

According to the _Windows Magazine_ article, Microsoft denies this is a
problem.  For the time being, you can:

1. Turn on the "Prompt for Summary Info" in the Tools/Options/Save menu (this
requires you to enter summary information, or accept what you've already
entered, each time you save the document.  This way Word will not lift
sentences out of the text.)
2. Block copy all your text to another document before transferring the file.
3. Notify Microsoft if you believe this is a problem, to encourage them
to fix it.

The RISKS? well ...
1. You start to write a flame-o-gram, but later tone it down.  Those
first sentences may still be buried in the document.

2. You're involved with sensitive information (competition sensitive, source
selection sensitive), or classified information.  You don't see anything
sensitive or classified so the document goes out.  But those first sentences
may still be there.

3. A software company sets their product to do something without telling you,
particularly something that uses information from you, in ways unintended by
you, without your knowledge or permission.

Chris Norloff

Report on the 1993 Gatwick near-miss

Peter Ladkin <>
Wed, 24 Aug 1994 20:42:35 +0200
   [NOTE: PGN introduced an error in the original copy of this,
   1992 instead of 1993.  That is corrected here.  PGN]

The accident report is now in on the February 1993 off-course Continental
Airlines Boeing 747 with 233 people aboard that flew within 500 feet of the
Gatwick passenger terminal during a landing attempt at Gatwick Airport.
Apparently computer failure prevented the automatic pilot from locking on to
the radio beams that would have guided the plane to the runway.  A manual
landing followed.  The crew had expressed doubts as to the accuracy of the
instruments.  [Source: A Close Call for U.S. Jet at Gatwick, excerpted by PGN
from The International Herald Tribune, 24 Aug 1994, p.2]

It sounds as though there was a failure to capture the localiser.  But that
happens. And how on earth were they following it if they hadn't captured it?
I'd also guess there was some discrepancy amongst the instruments that they
were busy trying to troubleshoot. Maybe one of the UK people can grab the
report?  Peter Ladkin

  [Also noted by Olivier M.J. Crepin-Leblond <>. PGN]

The new Cray and Unix passwords...

Peter Wayner <>
Fri, 19 Aug 1994 19:29:19 -0400
There has been a bit of news in the business sections about the new NSA
contract given to Cray to develop a hybrid machine that combined the
best of the old Cray vector approach with the best of the old Thinking
Machine CM-1/CM-2 architecture. It is somewhat ironic that this was
released in the same time frame that Thinking Machines went into Chapter
11, but it may turn out that this marriage really brings out the best
in both approaches. Some of the news stories concentrated on the
quasi-Chrysler-like bailout of an important technological treasure,
but that is a question for political scientists who cleave to moldy debates
about the relationship between private enterprise and the state.

The biggest question for citizens of the techno-tribe of cyberspace, though,
is what does this mean for digital privacy. Will the NSA be able to crack
passwords with abandon? Will they be able to cut through the protection of
DES like it was butter? Any speculation is, of course, pure speculation.
But it is possible to make some educated guesses about the machine.

News reports and other research states that this machine will include 512,000
processors that contain 256 bits of memory apiece. Each processor contains
an ALU and three one bit registers. It really isn't a processor as much as
a programmable logic gate that will take three inputs and spit out one of
the 8 possible outputs. The architecture is supposed to borrow heavily from
a neat machine called the Processor-In-Memory (PIM aka TeraSys) developed
by the Supercomputer Research Center, a semi-public branch of the NSA.

I happened to play with a very similar architecture several years ago
developed by a company called Coherent Research Inc in Syracuse, NY. It turns
out that it does a pretty good job of breaking DES.  One hypothetical machine
with 1 billion processors should be able to test all 2^(55) possible keys for
DES in 1 day.

How long should it take the Cray/SRC? The Cray/SRC processors are supposed to
run at 2.08 ns/cycle. The Coherent Chips ran at 50MHz or 20 ns/cycle.  This
means the Cray/SRC is about 10 times faster. This is a very rough estimate,
though, because it is not clear how many cycles it takes the Cray to complete
each operation. The Coherent Processor took 2-4 cycles per operation. This
would imply that the Cray/SRC could knock off all 2^{55} possible keys in 100

Given that DES may still be used extensively in financial transactions that
move billions of dollars, it becomes clear that it might be worth it to
spend $10 or so million on a machine and let it crank for a bit. (That's my
wild estimate on the price. I think it could be as low as $2-3 million).

But even if most of us don't have $100 million to steal, we still have
reason to wonder about the effects of this machine. UNIX security systems
use DES to encrypt the passwords 25 times before comparing them to a
encrypted version stored in the central password file. A popular attack on
the systems is to grab this central file and encrypt all of the words in
the dictionary looking for a match. This is easy to do with a garden
variety RISC machine today which is why many decent system administrators
require gibberish passwords with numbers.

How long would it take to attack gibberish passwords with this new
Cray/SRC? I extrapolated some earlier work of David Feldmeirer and Phil
Karn to show that a 64k processor version could knock off all 6 character
passwords in about half of a day. (6 characters drawn from the set
A-Z,a-z,0-9) If the 512k processor Cray/SRC can really run 10 times faster,
then it could knock off these 6 character passwords in less that 15
minutes. All seven character UNIX-style passwords would take less than 2
days and all eight could searched in less than four months.

There is one interesting side-effect of this approach. It takes about the
same amount of time to attack 1000 passwords as it does to attack 1. After
the 512k processors complete their encryption, they check to see if they've
got a match. The encryption process was about 10,000 times slower than the
matching on my design. So if you could grab a password file for a computer
with 1000 users it would still take you about 15 minutes to find the one
sucker with a 6 digit password.

This means that even the maximum-sized 8-character UNIX-style passwords are
really on the edge of obsolesence. It is really time for a new system to be
developed.  16 characters might be best. But who can remember that many?  Sure
some know millions of digits of pi, but a bunch of politicians tried to
shorten it to plain 3.  This means we need to rethink many of the modes of
protecting machines.

   [I presume that when Peter wrote "a plain 3" he was implying just 3
   digits, as opposed to the old mathematical physicists' joke about pi
   being equal to 3 for small values of pi and large values of 3.  PGN]

All of what I've written falls into the realm of informed speculation. You
can read about my design in a paper which was presented at Crypto 92. Mail
me if you want a TeX version of it. I suggest that you dig up conference
proceedings about the PIM/Terasys machine to get a better estimate of the
new Cray/SRC's machine's performance.

Most home security alarms are false

"Mich Kabay [NCSA Sys_Op]" <>
16 Aug 94 07:44:52 EDT
>From the Associated Press newswire (94.08.16 @ 00:00 EDST) via CompuServe's
Executive News Service (GO ENS):

"Home Security", By WILL LESTER, Associated Press Writer

The author describes the current problems caused by home security systems.
Key points:

o   Burglars can easily disable some home security system control panels.

o   Estimates of false alarms from these systems range from 70% to 90% and
even higher.

o   `"The false alarms are astronomical," says Sgt. Steve Emmons,
spokesman for the Tulsa, Okla., Police Department. "It ties up two officers
every time we get one, and 98 percent of our alarms are false. It is causing
our call load to grow to an extreme level."'

o   Dallas police field 140,000 alarms/year, "most of them false."

o   Los Angeles charges $80 per false alarm after the first four free false
alarms per location.

o   Miami tolerates five false alarms but then charge increasing fines.

o   Portland, OR. impose escalating fines and provide training.

o   "Security specialists advise buying a more sophisticated system that
can provide protection for windows, motion detectors and a control system not
easily disabled. Sirens are useful to shorten the burglars' stay."

M.E.Kabay,Ph.D./DirEd/Natl Computer Security Assn

<Philip Zimmermann, creator of PGP>
18 Aug 94
   [NOTE: PGN removed PZ's PGP signing, for brevity.  Besides, I
   corrected a few typos, which would blow the integrity check.  PGN]

I'd like to clear up some widely held misconceptions about PGP version 2.6
from MIT.  I get a lot of email and phone calls from people who report a lot
of misinformation on many Internet newsgroups about this MIT version of PGP.

(For those of you who need an introduction to Pretty Good Privacy (PGP), it is
a free software package that encrypts email.  PGP is the worldwide defacto
standard for email encryption.  It's available via FTP from,
in the pub/PGP directory.  But then, if you haven't heard of PGP, you don't
need to read this letter.)

Here is a list of misconceptions:

Myth #1:  PGP 2.6 is incompatible with previous versions.
Myth #2:  PGP 2.6 is weaker than previous versions, with a back door.
Myth #3:  PGP 2.6 was released without Zimmermann's cooperation.

All of these misconceptions would be cleared up if you read the PGP
User's Guide that comes with PGP 2.6, but a lot of people seem to be
spreading and believing these myths without looking into the matter
empirically and getting the new PGP and reading the manual.  Let's go
over these myths in detail.

- ---------------------------------------------------------
Myth #1:  PGP 2.6 is incompatible with previous versions.
- ---------------------------------------------------------

This is untrue.  PGP 2.6 will ALWAYS be able to read stuff from earlier

PGP version 2.6 can read anything produced by versions 2.3, 2.3a, 2.4, or 2.5.
However, because of a negotiated agreement between MIT and RSA Data Security,
PGP 2.6 will change its behavior slightly on 1 September 1994, triggered by a
built-in software timer.  On that date, version 2.6 will start producing a new
and slightly different data format for messages, signatures and keys.  PGP 2.6
will still be able to read and process messages, signatures, and keys produced
under the old format, but it will generate the new format.  This change is
intended to discourage people from continuing to use the older (2.3a and
earlier) versions of PGP, which Public Key Partners contends infringes its RSA
patent (see the section on Legal Issues).  PGP 2.4, distributed by Viacrypt
(see the section Where to Get a Commercial Version of PGP) avoids infringement
through Viacrypt's license arrangement with Public Key Partners.  PGP 2.5 and
2.6 avoid infringement by using the RSAREF(TM) Cryptographic Toolkit, under
license from RSA Data Security, Inc.

According to ViaCrypt, which sells a commercial version of PGP, ViaCrypt PGP
will evolve to maintain interoperability with new freeware versions of PGP,
beginning with ViaCrypt PGP 2.7.

It appears that PGP 2.6 has spread to Europe, despite the best efforts of MIT
and myself to prevent its export.  Since Europeans now seem to be using
version 2.6 in Europe, they will have no problems maintaining compatibility
with the Americans.

Outside the United States, the RSA patent is not in force, so PGP users there
are free to use implementations of PGP that do not rely on RSAREF and its
restrictions.  Canadians may use PGP without using RSAREF, and there are legal
ways to export PGP to Canada.  In environments where RSAREF is not required,
it is possible to recompile the same PGP source code to perform the RSA
calculations without using the RSAREF library, and re-release it under the
identical licensing terms as the current standard freeware PGP release, but
without the RSAREF-specific restrictions.  The licensing restrictions imposed
by my agreement with ViaCrypt apply only inside the USA and Canada.  It seems
likely that any versions of PGP prepared outside the US will follow the new
format, whose detailed description is available from MIT.  If everyone
upgrades before September 1994, no one will experience any discontinuity in

Some people are attracted to PGP because it appeals to their rebellious
nature, and this also makes them resent anything that smacks of "giving in" to
authority.  So they want to somehow circumvent this change in PGP.  Even
though the change doesn't hurt them at all.  I'd like to urge them to think
this one through, and see that there is absolutely no good reason to try to
get around it.  This new version is not "crippled" — in fact, it is the old
versions that are now crippled.  I hope that PGP's "legalization" does not
undermine its popularity.

This format change beginning with 2.6 is similar to the process that naturally
happens when new features are added, causing older versions of PGP to be
unable to read stuff from the newer PGP, while the newer version can still
read the old stuff.  All software evolves this way.  The only difference is
that this is a "legal upgrade", instead of a technical one.  It's a worthwhile
change, if it can achieve peace in our time.

Future versions of PGP now under development will have really cool new
features, some of which can only be implemented if there are new data format
changes to support them.  Like 2.6, the newer versions will still read the
older stuff, but will generate new stuff that the old versions can't read.
Anyone who clings to the old versions, just to be rebellious, will miss out on
these cool new features.

There is a another change that effects interoperability with earlier versions
of PGP.  Unfortunately, due to data format limitations imposed by RSAREF, PGP
2.5 and 2.6 cannot interpret any messages or signatures made with PGP version
2.2 or earlier.  Since we had no choice but to use the new data formats,
because of the legal requirement to switch to RSAREF, we can't do anything
about this problem for now.  Not many people are still using version 2.2 or
older, so it won't hurt much.

Beginning with version 2.4 (which was ViaCrypt's first version) through at
least 2.6, PGP does not allow you to generate RSA keys bigger than 1024 bits.
The upper limit was always intended to be 1024 bits — there had to be some
kind of upper limit, for performance and interoperability reasons.  But
because of a bug in earlier versions of PGP, it was possible to generate keys
larger than 1024 bits.  These larger keys caused interoperability problems
between different older versions of PGP that used different arithmetic
algorithms with different native word sizes.  On some platforms, PGP choked on
the larger keys.  In addition to these older key size problems, the 1024-bit
limit is now enforced by RSAREF.  A 1024-bit key is very likely to be well out
of reach of attacks by major governments.  In some future version, PGP will
support bigger keys.  This will require a carefully phased software release
approach, with a new release that accepts larger keys, but still only
generates 1024-bit keys, then a later release that generates larger keys.

- ---------------------------------------------------------------------
Myth #2:  PGP 2.6 is weaker than previous versions, with a back door.
- ---------------------------------------------------------------------

This is not true.  I would not allow MIT or anyone else to weaken PGP
or put a back door in.  Anyone who knows me will tell you that.

This is not to say that PGP doesn't have any bugs.  All versions have
had bugs.  But PGP 2.6 has no known bugs that have any net effect on
security.  And MIT should be releasing a bug-fixed version of PGP 2.6
Real Soon Now.

- ----------------------------------------------------------------
Myth #3:  PGP 2.6 was released without Zimmermann's cooperation.
- ----------------------------------------------------------------

Well, that's not true, either.  Or I wouldn't be telling you all this.

MIT did not steal PGP from me.  This was a joint venture by MIT and myself, to
solve PGP's legal problems.  It took a lot of maneuvering by me and my lawyers
and by my friends at MIT and MIT's lawyers to pull this off.  It worked.  We
should all be glad this came off the way it did.  This is a major advance in
our efforts to chip away at the formidable legal and political obstacles
placed in front of PGP; we will continue to chip away at the remaining

I hope this clears up the myths about PGP 2.6.  I urge all PGP users to
upgrade to the new version before September.  And I urge you all to use the
official 2.6 release, not anyone else's incompatible bastardized mutant strain
of PGP.  Please pass the word around, and help dispel these misguided rumors.
This letter may be (and should be) quickly reposted to BBS's and all
appropriate newsgroups.

 --Philip Zimmermann

<"Rob Slade, Ed. DECrypt & ComNet, VARUG rep, 604-984-4067">
Thu, 18 Aug 1994 14:25:22 -0600 (MDT)
Subject: "Secrets of a Super Hacker" by Fiery


Loompanics Unlimited
P.O. Box 1197
Port Townsend, WA 98368
fax 206/385-7785
"Secrets of a Super Hacker", Fiery, 1994, 1-55950-106-5, U$19.95

Despite Loompanics' reputation as a "dark side" publisher, this may be a very
good book.  It deals primarily with social engineering, despite the purported
coverage of other topics.  It would therefore be valuable reading material
around corporate lunchrooms, since forewarned is just a little bit more
paranoid and, therefore, forearmed.  As those involved with data security in
the real world well know, cracking is basically a con job.  Thus, The
Knightmare, if he really is "super", is a con artist par excellence--and is
pulling off a really great con here!

Revealing the secrets of social engineering poses very little threat to
security.  Con men already exist and will continue to exist.  Cracker wannabes
are unlikely to be able to carry off a successful con if they need to rely on
canned advice like this.  On the other hand, it is much more likely to shock
naive and non-technical users into an awareness of the need for suspicion and
proper procedures--albeit possibly only temporarily.  Thus, this information is
almost inherently of more use in data protection than in data penetration.

As for technical help for the cracker; well, are you really expecting great
technical revelations from someone who knows there is a difference between baud
and bits per second--and gets it backwards?  Or, who thinks 140 and 19,900 baud
are standard modem speeds?  Who thinks Robert Morris' worm found "original"
bugs?  (And who doesn't know the difference between "downgrade" and
"denigrate"?)  All the successful hacks in the book rely on social engineering
rather than technology.  Lots of jargon is thrown in along the lines of, "You
need X," but without saying what X really is, where to get it, or how to use

The official definition of a hacker in the book is of the "good side" seeker
after knowledge.  As it is stated early on, a hacker *could* do lots of
mischief--but doesn't.  In the course of the text, though, the image is much
more convoluted.  The book almost seems to be written by two people; one who is
within the culture and has the standard confused cracker viewpoint, and
another, sardonically aware of pulling the wool over all the wannabes' eyes.
The chapter on contacting the *true* hacker community is EST-like in its
refusal to define when you might have made it, or how.

Like I said, buy it for the corporate or institutional lunchroom.  Make sure
that the non-techies get first crack at it.  If you'll pardon the expression.

copyright Robert M. Slade, 1994   BKSCSUHK.RVW  940609

DECUS Canada Communications, Desktop, Education and Security group newsletters
Editor and/or reviewer,, Rob Slade at 1:153/733
DECUS Symposium '95, Toronto, ON, February 13-17, 1995, contact:

International Cryptography Institute

Dorothy Denning <>
Tue, 16 Aug 94 17:26:10 EDT
        International Cryptography Institute 1994: Global Challenges

                          September 22-23, 1994
                       Ritz Carlton, Washington, DC

                           Presented by
         The National Intellectual Property Law Institute

The International Cryptography Institute will focus on problems and challenges
associated with the use of cryptography within nations and for international
communications.  The Institute will address such questions as: What are the
different national policies and regulations governing cryptography and how
might these evolve?  What cryptographic technologies are on the market in
different countries, what is being used, and what is it being used for?  What
problems is cryptography causing law enforcement?  What are the requirements
of businesses and other organizations?  What are the new trends in
cryptography and what will be their impact on society?  What efforts are
leading toward an international cryptography framework?  The Institute is for
government officials, industry leaders, policy makers and analysts,
researchers, and users of cryptographic technologies.

September 22

8:45-9:00 Opening Remarks
Dorothy E. Denning, Chair of Program
James Chandler, President, National Intellectual Property Law Institute

The Challenges of International Crytography
Edward J. O'Malley, The OSO Group

Cryptography in the European Community
Christopher E. Sundt, ICL Secure Systems

Cryptography in the German Governmental Area
Ansgar Heuser, BSI

10:30-10:45 Break

Cryptography in Belgium
Els Lemmens, Belgian Office for Scientific, Technical and Cultural Affairs

The Use of Cryptography in Singapore
Kwok-Yan Lam, National University of Singapore
Seow-Hiong Goh, John Yong, National Computer Board

An Australian and South-East Asian View of Cryptography
William J. Caelli, Queensland University of Technology

12:15-1:45 Lunch with Keynote TBA

GSM: Security for World-Wide Mobil Radio
Charles B. Brookston, British Telecomm

International Exchange of Digital Signatures in a Diversified World
Jean-Jacques Quisquater, University of Louvain

Creating Global Cryptographic Infrastructures
Sead Muftic, Stockholm University

3:15-3:30 Break

An International Cryptography Framework
Keith S. Klemba and Jim Schindler, Hewlett-Packard Co.

Experiments in International Cryptography and Software Key Escrow
Stephen T. Walker, Trusted Information Systems, Inc.

International Escrowed Encryption
Dorothy E. Denning, Georgetown University
John Droge, Mykotronx, Inc.

5:00-6:00 Reception

September 23

U.S. Government Cryptography Policy
Michael R. Nelson, Office of Science and Technology Policy

Domestic Regulation of the Exportation of Cryptography
James Chandler, National Intellectual Property Law Institute

Sue E. Eckert, U.S. Department of Commerce

10:30-10:45 Break

Rose Biancaniello, U.S. Department of State (invited)

World-Wide Availability of Cryptography Products
David Balenson, Trusted Information Systems, Inc.

12:00-1:30 Lunch with Keynote
Louis J. Freeh, Director, Federal Bureau of Investigation

International Regulation of Cryptography
James Chandler, National Intellectual Property Law Institute
Alexander Patijn, Ministry of Justice, The Netherlands
William Wolfowicz, Fondazione Ugo Bordoni

2:45-3:00 Break

Cryptography in the Financial Industry
Mr. Mitsuru Iwamura, The Bank of Japan
Dr. Victor Panchenko, SignalRox, Russia (invited)
others TBA

  [Hotel and Registration info deleted.  Ritz Carlton has a SPECIAL CONF RATE
  of only $225 per night!  Tuition is $595.  E-mail Dorothy for details.  PGN]

Please report problems with the web pages to the maintainer