The Risks Digest

The RISKS Digest

Forum on Risks to the Public in Computers and Related Systems

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

Volume 13 Issue 24

Wednesday 4 March 1992


o Orange County Must Delay Stormwater Tax
Tanner Andrews
o Major software problems at TSE
Mark [with note from Bjorn Freeman-Benson]
o Garbage In, Gospel Out — genetic info
Vivek Khera
o 1-900 spelling game
Andrew Tannenbaum
o AT&T's operatorless collect calls
o Private SS Data Sold to Information Brokers
Chuck Lins
o RISKS of international trade negotiations: intellectual property, patents
Jyrki Kuoppala
o A320 and significance
Henry Spencer
o MAGSAV bug explained
Paul Eggert
o Re: Leap year strikes again
Rhys Weatherley
o Re: RSAREF license
David L. Black
o Re: Viruses
Bob Frankston
o Re: Virus news-bite omits crucial information
John Cav...
A. Padgett Peterson
Steve Milunovic
o Info on RISKS (comp.risks)

Orange County Must Delay Stormwater Tax

Dr. Tanner Andrews <>
Tue, 3 Mar 92 7:26:02 EST
The _Orlando Sentinel_ [remarkably acerbic comments about the paper have been
deleted by your immoderator] cost Orange County a year's delay in passing a
stormwater tax.  They failed to run two of the required advertisements for a
public hearing.

Yeah, ``it's the computer's fault.''

                   ...!{ allegra uunet!cdin-1}!ki4pv!tanner

Major software problems at TSE

Wed, 4 Mar 92 05:24:05 EST
         TSE computers go berserk, floor closed for four hours
         Breakdown bolsters opposition to computerized trading
         BY CAROLYN LEITCH, Toronto Globe and Mail,
         4 March 1992, business section, lead item

   A software glitch caused computers at the Toronto Stock Exchange to go
berserk yesterday, scrambling information, recording wildly inaccurate prices
and failing to print tickets to confirm trades.  Floor traders quickly used the
breakdown to bolster their opposition to the TSE's planned move next year to an
entirely computerized trading floor.  The malfunction also illustrated the
problems many organizations encounter when they try to change the software code
that instructs computers.

   TSE officials closed down floor trading for nearly four hours between 10 a.m
and 2 p.m. after irregularities were detected in the computer system that
traders use to buy and sell equities.  Carl Christie, a senior professional
trader with Nesbitt Thomson Deacon Inc. and chairman of the Professional
Traders Association, said he noticed dramatic problems shortly after the market
opened at 9:30 a.m.  An order to buy 20,000 shares in Teck Corp. at $17.37 a
share appeared on the computer as a bid for 3,339 shares at $279.50 a share, he
said.  As well, some sellers were unaware their sell offers had been accepted
because the system was not printing confirmation tickets.

   The TSE said it didn't know if it would have to unwind any of the trades.
The exchange said disputes over orders that went awry will be decided on a
case-by-case basis by floor governors.  Mr. Christie said that as as
specialized trader with certain stocks, he had no flow of orders coming in
during yesterday's shutdown.  As many as 150 other traders were also affected,
he added.  "I know that it cost me money — we lost two-thirds of our working

   The TSE has voted to replace floor trading with a fully computerized system
early in 1993.  That decision is unpopular with floor traders who fear for
their jobs.

   The bugs appeared after the TSE changed its computer software over the
weekend to deal with new trading rules.  Olaf Kraulis, vice-president of
information systems at the TSE, said the system was restored to its pre-weekend
state after flour hours of grappling with the problem.  He said the software
changes will be reinstated in one or two weeks after programmers figure out why
they fouled up the computer system.

   But Don Unruh, a former TSE vice-president who helped develop the system
eight years ago, said the problems run deeper than yesterday's malfunction.  A
patchwork of different software and hardware has emerged over the years, he
said.  "The people who are making the changes eight years later have no idea
what was done by the people who went before them.  You end up with these
bizarre logic problems."  Mr. Unruh, now a consultant who recently wrote a
report on the TSE's computers for the Professional Traders Association, said
the whole system should be scrapped and a new one developed.

   But Mr. Kraulis said thousands of changes are made to software every year
with few problems.  While the 12 Tandem Computer processors that power the
system have backup provisions in case of a hardware failure, there is no such
contingency for software problems.  "If a copy of the software is wrong, every
copy will be wrong," he said.

   Leonard Petrillo, the TSE's vice-president of corporate affairs, said the
impact on members was minimal.  "Most of the stocks are inter-listed," Mr.
Petrillo said, "and traders were able to instantaneously reroute orders to
other exchanges," such as the Montreal Exchange and the New York Stock
Exchange.  [...]

           [Also submitted by bnfb@csr.UVic.CA (Bjorn Freeman-Benson),
           who added this:]

    [The RISKS?  Besides the obvious ones, the interlisting could motivate
    traders to avoid an unreliable Toronto in favor of Montreal, which is a
    risk to the computer owners rather than the computer users...  Bjorn]

          [How about the risk of sabotage by dissident floor traders?  PGN]

Garbage In, Gospel Out — genetic info

Vivek Khera <>
Wed, 04 Mar 92 13:39:16 EST
Summarized from the March 2, 1992, Newsweek, page 58: "Eve Takes Another Fall"

In 1987, a group at UC Berkeley used a computer to analyze mitochondrial DNA
from 147 people and proclaimed that all humankind descended from one woman who
lived in Africa 200,000 years ago.  Last year the team ran a more rigorous
analysis using 189 samples and again concluded the same thing.

The program tries to find the family tree that is most "parsimonious"; that is,
a tree based on the fewest genetic mutations.  The trouble is that there are
multiple equally parsimonious trees, and no algorithm to guarantee the computer
has found the best one.  The resulting tree depends on the order of the data
input.  The Berkeley group assumed the order of data was irrelevant.  "They
weren't using the program in an adequate way," says Alan Templeton of
Washington University.

One explanation of why it took so long to discover this error: ``...[they]
didn't have the mathematical savvy to understand the statistical traps in the

               [... cloning primordial parsnips in a pearsimonious tree?  PGN]

1-900 spelling game

Andrew Tannenbaum <>
Wed, 4 Mar 92 14:38:50 -0500
There is an ad on TV for a 1-900 telephone service spelling game - if you can
spell twenty words correctly in two minutes, you win $200.  I guess you hear
the words and type them in on your touchtone pad.  Assuming that the game isn't
rigged to make it impossible to win, it would be pretty easy to devise a hack
to allow you to type words on your PC, check their spellings, and send out the
correct touch-tone signals on the fly.

The parts for this hack are readily available.  There are good spell
checkers and big dictionaries (word lists).  Modems these days have
dialers that generate touch-tone, it ought to be possible to program
them to talk to the spelling game (sending tones at the proper speed
and spacing).  I imagine that this computer-aided approach would
improve your odds to a significant extent.

    Andrew Tannenbaum   Interactive   Cambridge, MA   +1 617 661 7474

AT&T's operatorless collect calls

"Peter G. Neumann" <>
Wed, 4 Mar 92 18:33:33 PST
Andrew's message reminds me of this morning's news item that AT&T will need far
fewer operators because it is automating voice processing to eliminate some
operator assistance.  (The scheme is already being tested in various areas.)
The collect call initiation permits the caller to pack an arbitrary short
message into the time slot for the caller's presumed name.  I imagine that will
open up all sorts of new games that are currently prevented by operator
assistance.  On the other hand, it has always been possible to do that now with
a little prearranged coding.  With the new scheme, you would not even have to
resort to Tuesday Weld to anticipate arrival in Maine, Gal Friday to indicate
Galveston, etc.)  It would seem to be much more flagrant with the new scheme.
So, maybe they will try to filter out strange sequences.  Blocking short bursts
of 2.4Kb data transmissions might be possible, for example!  But it would be
terrible to restrict it to small dictionaries like telephone book names
suitably pronounced without too much of an accent.  This sounds like a freebie
fraught with fraud, I'm afraid.

Private SS Data Sold to Information Brokers

"Chuck Lins" <>
4 Mar 92 08:12:32 U
Private SS Data Sold to Information Brokers
San Jose Mercury News, Saturday February 29, 1992.

Private Social Security data sold to 'information brokers'
By R.A. Zaldivar, Mercury News Washington Bureau

Washington - The privacy of 200 million Americans with records at the Social
Security Administration is threatened by an illegal trade in pilfered computer
files.  Computerization has dramatically improved our ability to serve the
public," Social Security Deputy Commissioner Louis Enoff told a Senate panel
Friday.  "However, it has also made confidentiality more difficult."

Two executives of Nationwide Electronic Tracking, a Tampa, Fla., company,
pleaded guilty to conspiracy charges in January for their part in a national
network selling Social Security records.  Twenty-three people, including agency
employees and police officials, have been indicted in the case - the largest
known theft of government computer data.  "Information brokers" will pay Social
Security employees $25 for a person's earnings history and then sell the data
for as much as $300. Their growing list of customers includes lawyers, private
investigators, employers, and insurance companies.

Social Security records contain a mother lode of information that includes not
only a person's past earnings but names of employers, family history and even
bank account numbers of people who receive benefits by direct deposit.  The
information can be used to find people or to make decisions on hiring, firing,
suing or lending, said Larry Morey, deputy inspector general of the Health and
Human Services Department.

"Here we have a large-scale invasion of the Social Security system's
confidentiality," said Sen. Daniel P. Moynihan, D-N.Y., chairman of the Social
Security subcommittee.

Information from other government data bases with records on individuals - such
as the FBI's National Criminal Information Center - is also available on the
underground market. All a broker needs is the cooperation of a clerk at a
computer terminal.

Congress may revise privacy laws to increase penalties for illegally disclosing
information in the private files of individuals.

Enoff said Social Security is studying ways to improve computer security, as
well as keeping closer tabs on employees with access to files, and stressing to
its workers that unauthorized disclosure of information is a federal crime.

  Perhaps if release of information was keyed to a digital signature of the
  [clerk, this could be used to identify those persons (at SSA) selling the
  information. No mention is made of the buyers of the information from the
  broker. I guess they just get to keep the illegally obtained information.

  Now I wonder what happens when this happens in California at the DMV, and a
  copy of my digitized signature is sold?  Chuck Lins]

RISKS of international trade negotiations: intellectual property,patents

Jyrki Kuoppala <>
Wed, 4 Mar 1992 17:59:38 +0200
There has been an attempt in the UN organisation World Intellectual Property
Organization, WIPO, to harmonize world's patent laws.  It seems to be that USA
is just about the only country who is pressing for "patents on all fields of
technology" while many countries oppose things like patents on software and
biotechnology.  The developing countries say that many patents are one of the
Western worlds' ways of keeping ahead in the game and keeping the developing
countries behind.

In UN, it's one vote per country so USA has not been very successful.  However,
USA seems to have more success via GATT, as Kurt Jaeger writes on

"Look e.g. on [] in directory
info/comp.patents/lpf-de/docs/GATT-draft.txt.Z, its a copy of the TRIPS stuff
in the GATT treaty (TRIPS == trade <something> intellectual property 

A320 and significance (Ilieve, RISKS-13.21)

Wed, 4 Mar 92 18:33:23 EST
>Unless you assume that the pilots flying A320s are more stupid than
>average, then if pilots have more crashes in A320s than other planes,
>even if the cause is officially `pilot error', there must be something
>about the plane that makes errors more likely.

My statistics friends would laugh at this, or sigh and shake their heads.
The proper version is "...if pilots have *significantly* more crashes...".

One must remember that COINCIDENCES DO HAPPEN.  Remember the time
some years ago when it seemed that whenever you turned on the radio,
there was another report of a DC-10 crash?  Haven't heard many lately,
have you?  What changed?  Basically, nothing.  Oh, some minor changes
were made in the aircraft and its operating procedures, but that spate
of crashes was mostly sheer bad luck.  Modern airliners very seldom
crash; the DC-10 just had a couple of bad years, with mechanical flaws,
bad maintenance, navigation problems, and (yes) pilot error all striking
down the same type of aircraft at around the same time.

It's still actually open to doubt whether the DC-10 is significantly less
safe than its competitors.  The numbers do suggest so, but they are based
on so few incidents — compared to the enormous number of successful and
uneventful flights — that it is entirely possible that the DC-10 has
simply had bad luck.  In military flying, with much higher accident rates,
it is not at all uncommon for the investigation of a series of accidents
to find that the failures were unrelated and the timing just coincidence.

On the whole, I think there is some reason to suspect that the A320 has
human-interface problems.  But that conclusion is based on the *details*
of the cases so far, not on just counting them.  It will be quite a while
before we have enough data on A320 crash rates to start to draw any valid
numeric conclusions about whether it really crashes unusually often.

                        Henry Spencer at U of Toronto Zoology  utzoo!henry

MAGSAV bug explained

Paul Eggert <>
Tue, 3 Mar 92 18:27:55 PST
G M Lack reports in <>
that MAGSAV probably failed on 29 Feb 1992 because it tried to increment
the year by one to set a tape label expiration date,
and the resulting nonexistent date 29 Feb 1993 threw it for a loop.
Alas, dates are tricky, and that goes double for date arithmetic.

Re: Leap year strikes again

Rhys Weatherley <>
4 Mar 92 03:23:50 GMT
I too experienced strange behaviour with Feb 29 dates.  A Windows 3.0
newsreader I have been prototyping using Borland C++ 2.0 has been happily
chugging along for a number of weeks without hassle.  Then (of course) it
locked up for no apparent reason.

Tracing the program revealed that during the parsing of "Date:" headers, when
it called the "mktime" function to convert the dates to the Unix date/time
format, it locked up.  I haven't delved deeply into disassembling the code for
"mktime", so I don't know the exact cause of the problem, but the call was
very quickly replaced with an alternative version of "mktime". :-)

So, some of these problems; at least on PC architectures; may be attributable
to bugs in the run-time libraries of Borland C++ and possibly Turbo C++ also,
rather than to the authors of packages that use the run-time libraries.

Rhys Weatherley, The University of Queensland, Australia

Re: RSAREF license

Wed, 4 Mar 92 14:36:09 GMT-0400
Shortly after this electronic license agreement showed up inside OSF,
we received a missive from our attorney asking in no uncertain terms
that we not execute the license (and revoke it and dispose of the
software if we had).  The major problem revolves around the fact that
the technology is export controlled.  The original posting stated:

>    4.   You can't send RSAREF outside the United States, or give it
>         to anyone who is not a United States citizen and doesn't
>         have a "green card." (These are U.S. State and Commerce
>         Department requirements, because RSA and DES are
>         export-controlled technologies.)

The problem is that the intuitive meaning of this paragraph is misleading.  The
intuitive meaning is that you must not intentionally do something that
explicitly transfers the software to someone who should not have it (for
brevity, call this individual a `restricted person').  Unfortunately, the
actual restriction includes unintentional acts, and acts of omission (didn't do
something you should have).  An example could be include putting the source
files on a system to which a restricted person has access (unbeknownst to you).

If something goes wrong, the government may come after both you and your
employer (by holding your employer responsible for your actions).  At the very
least, anyone contemplating putting this software on one of their employer's
systems should run the license past the appropriate lawyer.  There are other
more mundane reasons for a lawyer to say no, such as needing to formally verify
that RSA really is who they say they are.

The RISK here is that the quasi-public distribution mechanism being set up by
RSA may well be inappropriate for export controlled software.  This is not like
the copyright laws; people go to jail for violating export control laws.

Disclaimer I: This post is a statement about the export control laws; it has
nothing to do with my views about how distribution of this software should (or
should not be) controlled.  If you've ever wondered about the restrictions that
export control laws place on information interchange and technology transfer,
you now have a concrete example.

Disclaimer II: Nothing in this post should be relied on as legal advice.  If
you think you might have a problem, go find a real lawyer.

--David L. Black (

... viruses

Tue 3 Mar 1992 21:34 -0500
It is not public, but at least one large software company does put in some
integrity checks in its software.  While this isn't Virus protection, it is a
step in the right direction.

I wonder if a more technical term like "Transportable Boot Sector Modification
Programs" would engender the same amount of popular press.  Question: How many
people are going to start wearing gloves when they use their computers?

It is also interesting that an MSDOS Virus is getting this attention.  Macs
are actually more vulnerable since the passive insertion of a disk will cause
the execution of a procedure whereas you must execute off the disk in order
to run program on it.  I presume that the larger number of PC users and,
perhaps, more of a history of exchanging programs contributes to the spread.

The infection is actually worse in object-oriented systems since objects are
active elements (i.e., they come with methods and behaviors.  One can argue
that any object IS a kind of Virus that comes with its executable code and
relies on the local environment to give it life.  Dealing with issues like
this is what delays seemingly good ideas.  In fact, over 25 years ago, there
was to be T access in Multics.  T stood for "Trap".  When you attempted to
access a segment with Trap access, a trap routine, provided by the segments
owner would be run.  Of course, it would have to be run in the owner's access
domain with the user protected from bad behavior though the trap procedure
would also be executing in some form of the user's environment.  No surprise
that T access didn't make into the (relatively) secure production system.
But the thinking raise issues of mutually suspicious subsystems generating
various theses.  One indirect result is the ring architecture of the 386. The
moderator and other readers can contribute many more details to this history.

By being naive, the Mac was able to implement a very user-friendly feature.
A smart disk allows one to insert a disk and let it install itself.  Only
etiquette demands that it should ask permission before starting.  The Mac
also naively implemented bitmap fonts on a fixed size screen.  Scaleable
fonts weren't even imagined by most users.

So which is right — the Multics approach of implementing a feature after it
is somewhat understood or the Mac approach of doing what makes things easy
for the user and then fixing it up later.  Novell implemented a remote file
system by patching into DOS in a way that 3com didn't.  As a result, people
bought Novell's product and Microsoft has to accommodate them.  Cellular
phones with their lack of security are another example.  Conversely, all
electronic devices brought onto airplanes are, for some reason, suspect.
Apparently turning them on at a security point exorcises the daemons...

In the case of viruses, we might achieve a balance of terror by hanging a few
creators (chosen by lottery) by their typing fingers and hoping the problem
abates.  Some firewalls will be added to software.  The alternative of
creating truly secure software is possible — just prevent naive users from
getting near computers.

Re: Virus news-bite omits crucial information

Wed, 04 Mar 92 11:45:17 -0600

I wish to apologize for the extremely poor wording of my original article.  The
point I was trying to make was that the Michaelangelo virus does NOT attack
Macintoshes, Amigas, SUN workstations, UNISYS mainframes, etc. etc., but the
radio program made no mention of any such distinctions.

I used the phrase "MS-DOS clone machines" to mean IBM PC-compatible computers.
I should have said that instead.  Oh well.


     [There was a slew of messages on this subject, including those from
        Bennet_Yee@PLAY.TRUST.CS.CMU.EDU, (A. Padgett Peterson), (Jim Thompson), (Tom Neff), (David Holland), and (Robert Slade).
     I could not include them all, but there was lots of overlap.
     However, I pseudorandomly picked Padgett's, which follows.
     Read no further if you have had enough.  And then wait for Friday.
     Thanks to all of you for rising to the occasion.  PGN]

Michelangelo & Unix Boxes

A. Padgett Peterson <>
Wed, 4 Mar 92 09:00:54 -0500
>That's a pretty amazing feat, since to do this, ...

Unfortunately, it is no problem at all since Michelangelo is a BIOS virus (no
it doesn't infect the BIOS, it uses it) and this is present and essentially
standardized (what makes a PC "100%" compatable) in every Intel box that is
able to boot DOS.

The virus uses Intel iapx80x86 assembly language but only uses BIOS interrupts
not MS-DOS interrupts (my FixMBR does also which is why it can repair "invalid"
disks but needs DOS to load the program).

The important fact is that when a PC frst loads absolute sector 1 from a disk,
it is already, courtesy of the BIOS, a fully functioning computer with the
ability to address all of its peripherals. It is just not yet a MS-DOS (or
PC-DOS, or OS/2, or Unix, or...) computer yet. The original Flight Simulator
and many DOS 1.0 programs (the ones you had to boot from the floppy but were
unreadable by DOS) were examples of BIOS-only programs.

Unfortunately, except for a few of us -and many virus-writers 8*( -this seems
to be a "lost art".

The problem that Michelangelo has stems from things it expects that are
characteristics of DOS and are not necessarily true:

1) That absolute sector 7 on the fixed disk is unused
2) That memory marked in software as "unavailable" by the BIOS will not be used

Neither assumption is necessarily true under Unix though it is usually (1)
that causes Mich (or Stoned or ...) to fail on a Unix platform by making it

BTW IMHO any damage that results from Michelangelo may be laid directly at
the feet of the OS vendors for Intel based platforms (and this includes
UNIX as well as DOS) who do nothing about "rogue programs" at the BIOS level
(over 50% of all reported infections last year)

Ten bytes in IO.SYS (or the boot record, or the MBR like my stuff) are all that
is necessary to find every MBR infector that I have come across including
Brain, Yale, Aircop, Stoned, Evil Empire, Bloody, and many others including
the Michelangelo.

The question is: if we do not take steps now to eliminate these viruses,
what are we ever going to do about the really nasty and professional (the
Michelangelo is very buggy & "crude") viruses that I know could be written ?



"Steve Milunovic" <>
Wed, 4 Mar 92 9:55:36 PST
I wish there was some way to stop the media from spreading such bad advice
as resetting the clock to circumvent the Michelangelo and other date virus
strains. Don't they know the virus is still there and can become more
widespread if it isn't removed? =Steve=

Please report problems with the web pages to the maintainer