The RISKS Digest
Volume 9 Issue 62

Friday, 26th January 1990

Forum on Risks to the Public in Computers and Related Systems

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

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Australian medical database linkages
Michael Bednarek
Cause of AT&T network failure
Jim Harkins
London Stock Market Disruption
courtesy of Steve Milunovic
Railway interlocking
Clive Feather
More risks to computers
Richard Thomsen
Re: Risks of supermarket checkout scanners
Marvin Moskowitz
Doug Renner
Don Craig
Robert T. Morris Convicted
Michael J. Chinni
Advance Program for Oakland Symposium (REVISED)
Debbie Cooper
Info on RISKS (comp.risks)

Australian medical database linkages

Michael Bednarek, Melbourne University <>
Tue, 23 Jan 90 13:32 +1100
                             Database `akin to ID card'
                                   by Tony Healy
                           (The Australian, 23-Jan-1990)

Incensed pharmacists have forced the deferral of a nationwide computer network
which they say has many features of the Australia Card. [A national ID card
scheme whose introduction was recently abandoned] According to confidential
documents obtained by _The Australian_, the proposed network will record
every medical prescription issued to every individual and family in Australia
during long periods of time.  It will thus form a detailed and easily accessed
record of personal illness and disease.

Although the network has received little publicity, it was originally scheduled
to start operating on a pilot basis in April and to be fully operational by the
end of the year.  It is to be implemented by the same government body that
wanted the Australia Card — the Health Insurance Commission — using the same
computers it bought for the Australia Card.

Most controversial of all is the commission's intention to link its database
with that of the Department of Social Security.  This intention is explicitly
stated in the documents held by _The Australian_ — a Health Insurance
Commission report titled Strategy Proposal for the Management of the
Pharmaceutical Benefits Program.

In the report, the commission also proposes making its network available on a
commercial basis to pharmaceutical suppliers.  Such a link realises the worst
fears of civil libertarians, who contend that the centralisation of information
and high speed access exposes information to abuse.

Both the Pharmacy Guild and the Australian Medical Association (AMA) have
objected to the risk this poses to patient confidentiality.  Guild protests
forced the commission to postpone the introduction of the network by six
months., its president, Mr Jim Mathews, said.

The federal president of the AMA, Dr Bryce Philips, said the association has
sought formal assurances from the commission that patient confidentiality can
be guaranteed.  "If it can't, we will not be part of it," he said.  A pointer
to the furtiveness surrounding the network is that the AMA learned about it
only by chance late last year, Mr Mathews said.  In its report, the Health
Commission also states its intention to create a culture in which people carry
an identifying card.

Confidential tender documents issued by the commission call for the network
eventually to be able to accept magnetic stripe cards.  In addition, the
commission recently tried to expand the information it gathers from concession
application forms.

Pharmacists point out that the extra information gives the Government the same
information it wanted to record on the Australia Card and have refused to
provide it.

The rationale behind the network is to reduce an estimated $[AUS]30 million
worth of pharmacy benefits fraud identified in report by the Attorney General.

The network will consist of online terminals in each of Australia's 5500
pharmacies, connected to a central database running on the commission's two IBM
3090 mainframes.

Before issuing prescriptions, pharmacists will be required to check all
customers on the computer. A principal reason is their eligibility for
pensioner and other concessions — this concerns about 80 per cent of
prescription customers.

A spokesman for the Federal Minister for Community Services, Mr Staples, denied
the claims and described them as part of pharmacists' heated campaign against
the Government.

Michael Bednarek, Big River Ski Lodge Caravan Park, Seelands via
Grafton NSW 2460, Australia,   Phone: +61 66 {44 9324 | 44 9200}
u3369429@{ |}   |

       [Also submitted by (Rev Dr Phil Herring) ]

Cause of AT&T network failure

"Peter G. Neumann" <>
Fri, 26 Jan 90 14:24:30 PST
From Telephony, Jan 22, 1990 p11:

    "The fault was in the code" of the new software that AT&T loaded
    into front-end processors of all 114 of its 4ESS switching systems
    in mid-December, said Larry Seese, AT&T's director of technology
    development. In detail:

    The problem began the afternoon of Jan 15 when a piece of trunk
    interface equipment developed internal problems for reasons that
    have yet to be determined. The equipment told the 4ESS switch
    in New York that it was having problems and couldn't correct the
    fault. "The recovery code is written so that the processor will run
    corrective initialization on the equipment. That takes four to six
    seconds. At the same time, new calls are stopped from coming into the
    switch." Seese said.

    The New York switch sent a message to all the other 4ESS switches
    it is linked with that it was not accepting additional traffic.
    Seese referred to that message as a "congestion signal."  After
    the switch successfully completed the reintialization, the New York
    switch went back in service and began processing calls.
    That is when the fault in the new software reared its ugly head.
    Under the previous system, switch A would send out a message that
    it was working again, and swithc B would double-check that switch
    A was back in service. With the new software, switch A begins
    processing calls and sends out call routing signals. The reappearance
    of traffic from switch A is supposed to tell switch B that A is
    working again.

    "We made an improvement in the way we react to those messages so
    we can react more quickly. The first common channel signaling system
    7 initial address message (caused by a call attempt) that switch B
    receives from swithc A alerts B that A is back in service. Switch B
    then resets its internal logic to indicate that A is back in service,"
    said Seese.

    The problem occured when switch B got a second call-attempt message
    from A while it was in the process of resetting its internal logic.
    "[The message] confused the software. it tried to execute an instruction
    that didn't make any sense. The software told switch B `My CCS7 processor
    is insane'", so switch B shut itself down to avoid spreading the problem,
    Seese explained.

    Unfortunately, switch B then sent a message to other switches that it
    was out of service and wasn't accepting additional traffic. Once switch
    B reset itself and began operating again, it sent out call processing
    messages via the CCS7 link. That caused identical failures around the
    nation as other 4ESS switches got second messages from switch B while
    they were in the process of resetting their internal logic to indicate
    switch B was working again.

    "It was a chain reaction. Any switch that was connected to B was put
    into the same condition."

    "The event just repeated itself in every [4ESS] switch over and over
    again. If the switches hadn't gotten a second message while resetting,
    there would have been no problem. If the messages had been received
    farther apart, it would not have triggered the problem."

    AT&T solved the problem by reducing the messaging load of the CCS7
    network. That allowed the switches to rest themselves and the network
    to stabilize.

Re: AT&T Failure

Jim Harkins <jharkins@sagpd1.UUCP>
23 Jan 90 12:39:43 PST (Tue)
>The assertion by AT&T, "in an effort to allay customer fears about the networks
>reliability," that the outage was "traced to a single computer program," not
>only fails to reassure me, but alarms me greatly.  It suggests a serious
>failure on their part to understand the nature of the problem.

I think you need to remember that this failure report was intended for the
great unwashed, who relate the term 'computer' to their Apple II, or possibly
the protagonist in the movie 'The Demon Seed'.  It is clearly inadaquate for
those of us who are technically literate.  I for one am looking forward to
reading in Risks and similar technical journals what really happened.

London Stock Market Disruption

Steve Milunovic <>
26 Jan 90 09:37:59
Trading on the London Stock Exchange suffered a minor disruption on 23 Jan 90
when a computer problem interrupted the quotation of the stock exchange market
indexes for two hours and 20 minutes.  The problem was spotted when The
Financial Times-Stock Exchange index of 100 leading stocks suddenly went from a
slight gain to a noticeable loss. The exchange shut down the index service at
noon, installed a standby computer and began operating the service again at
2:20 p.m.  The exchange's automated computerized trading system was not
affected, and individual stock quotes were accurate.  [Source: N.Y. Times News
Service, 23 Jan 90]

Railway interlocking

Clive Feather <clive@ixi.UUCP>
Tue, 23 Jan 90 10:08:23 gmt
I felt I had to say a few things about Douglas Jones' item in RISKS 9.58.
Whilst I realise that UK and US usages may be different, I think that some of
these points may be of interest to all readers anyway.

> (One at a time because it takes his full strength ...)
Some levers control the signal or points electrically, and so require almost
no effort. For this reason, the lever handle is cut short so that only one
hand can be used on the lever. Nevertheless, the signalman will only operate
one lever at a time.

In large boxes, two or three signalmen may work a single frame ("frame" is the
UK term for the row of levers). In this case, it is possible for two or more
levers to be operated at the same time. This was a contributing factor to the
accident at Hull (Paragon).

[Note to PGN: mailed you and me a description of this about two
years ago. If you or he still has it, it might be worth posting it to RISKS.]

> (I've seen photos ... with banks of 20 or more control levers.)
In the UK, 20 levers would be regarded as a small frame (and so low paid!). A
typical main-line box would have 50 to 60 levers, and a large one could have
two frames of 120 levers each. This makes the interlocking problem
considerably more complex.

> ... thus, there are 256 possible states of the system.
> An interlocking machine consists of a set of 8 transverse rods crossing 8
> rods linked to the control levers.
It would be unusual for there to be exactly 8 transverse rods, or "tappets" as
they are known. Each tappet implements one condition in the interlocking. It
is not sufficient to consider the static states, as there are many
circumstances when a *change* must be forbidden (e.g. don't move 2 if 1 is up,
even though either state of 2 is legal when 1 is up). In the example given, the
conditions, one per tappet, would be:

    1, 3, 4 down to move 2
    5, 6, 8 down to move 7
    3 up only if 2 set to straight through
    4 up only if 2 set to loop
    5 up only if 7 set to straight through
    6 up only if 7 set to loop
    1 up only if 3 and 4 down
    8 up only if 5 and 6 down
    1 and 8 cannot both be up

Thus 9 tappets would be required. (The last condition implements a general
rule that trains are never allowed into a passing loop from both directions at
the same time).

(Of course, this layout would not be implemented as such. Firstly, the points
would have locks, each controlled by their own lever. Secondly, two further
signals would be placed at the same locations as 1 and 8, but applying in the
opposite direction, so that a train can be shunted between the two sides of
the loop without leaving the area controlled by the signal box. Thirdly, these
two signals would be electrically interlocked with equipment which ensures that
a train cannot be signalled on to a single line which is already occupied.
Fourthly, there would be distant signals about a mile before 1 and 8, which
show only "caution" and "clear"; these could only show clear if the points are
set for straight through running, and all signals in that direction are at
"go". Finally, a King lever would be installed to allow the box to be unmanned
at night; when the lever is pulled, it is possible to clear the signals in
both directions at the same time, notwithstanding the interlocking, and the
signal boxes on either side would be connected to each other as if this one
was not there. So in fact we would have 13 levers, probably about 18 tappets
(I haven't worked it out), and some electrical interlocks (see below). But
this is starting to sound like rec.railroad :-)

Modern practice in lever frames (which are slowly being phased out) is to use
electrically controlled bolts as well as or instead of tappets to lock the
levers. This allows practices such as:

    - don't allow a signal to be raised without permission from the next
      signal box down the line;
    - ensure that permission applies for "one pull only", and that the signal
      must be replaced before permission can be given again;
    - only allow the exit signal to be raised if a "token" has been issued for
      the single line section ahead; two signal boxes are connected so that
      only one token can be issued at a time (the token may be physical or
    - ensure that a train has occupied and cleared a specific track circuit
      before the signal can be cleared again ("Welwyn control").

The Farnley Junction accident (RISKS-5.66, 30 Nov 87) shows that safety
critical software problems are nothing new (the accident occurred because NOT
NOT X equals X), and railways do indeed have something to teach us.

Clive D.W. Feather, IXI Limited   ...!uunet!ukc!ixi!clive (riskier)

More risks to computers

Richard Thomsen <rgt%beta@LANL.GOV>
Mon, 22 Jan 90 08:25:52 MST
A friend of mine worked as a computer operator in a company with a large IBM
computer.  One day, they called in the repairman for a faulty console.  When
the repairman arrived to check out the problem, he noticed that some of the
keys of the console keyboard were stuck down, in the shape of a closed fist.
His comment: "We can fix this, but it will not be under warranty."
                                            Richard Thomsen

Re: Risks of supermarket checkout scanners (Marks, RISKS-9.61)

Marvin Moskowitz <marvinm@ttidca.TTI.COM>
22 Jan 90 23:47:21 GMT
>I seems to me that consumers accept the technology not because they feel
>it is accurate, but because it makes checkout faster.

It seems to me that consumers accept the technology because they have no
choice. The only markets in Los Angeles that DON'T use automated scanners are
small convenience stores (e.g. 7-11).  If you want to buy food, you HAVE to
accept the scanner system.  My wife has objected to the lack of marked prices,
preventing her from checking the receipts.  I have suggested she take a pen to
the market and mark the prices as they come off the shelf. The only problem is
a fair percentage of the shelf prices are missing, which I imagine IS a
violation of some law. Go tilt at windmills!

Marvin S. Moskowitz, Citicorp/TTI, 3100 Ocean Park Blvd.,Santa Monica, CA 90405
(213) 450 9111 x3197                       {philabs|csun|psivax}!ttidca!marvinm

Re: risks of supermarket checkout scanners

Doug Renner <>
Tue, 23 Jan 90 11:48:30 CST
It may very well be the case that people accept the technology because they
feel it is more accurate.  The real issue is that this 'feeling' may be
unfounded, or based primarily on marketing hype.

UUCP: {amdahl!bungia, uunet!rosevax, chinet, killer}!orbit!pnet51!elec
ARPA: crash!orbit!pnet51!       INET:

Re: Risks of supermarket checkout scanners

Don Craig <>
Mon, 22 Jan 90 16:11:44 PST
David Marks quotes an INSIGHT magazine article: "Retailers contend that just as
many pricing errors are made in favor of the customer..."  What then should the
attentive shopper, checking his prices, do when he sees an UNDERcharge go past?
My conscience is regularly stricken when I shop at the local purveyor of
organic and transitional organic foodstuffs.  Service ranges from pleasant and
ineffectual through bossy and dumb, checkout pricing is by seminumerate human
being.  I buy Thomas Hardy's ale there, which costs $2.89 for a 6 ounce bottle,
or $11.56 for a carton of 4.  Each bottle is marked $2.89, but the carton price
appears nowhere.  If asked by the checkout clerk I tell them the price is
$11.56, but if they don't ask I accept what they charge.  About half the time,
it's $2.89 for the whole carton.  I tell myself this makes up for the utter
incompetence of say, the organic meat department, but I still feel guilty when
I leave.  What should I do?  ...Distressed in Oregon

    [Perhaps it is really Oregonic meat, not Organic meat, and someone is
    illiterate as well as innumerate.  Perhaps you should switch to Samuel
    Adams beer.  Although Hardy was more literate, Adams might have been more
    patriotic.  But you could have a nice chat with the manager.  You will
    probably find that the hearty ale is not Bar Coded.  (HardyHar at your
    neighborhood bar.)  PGN]

Robert T. Morris Convicted

"Michael J. Chinni, SMCAR-CCS-E" <mchinni@PICA.ARMY.MIL>
Tue, 23 Jan 90 9:52:55 EST
The following is an excerpt from a message sent by one of our computer security
people.  Michael J. Chinni, Picatinny Arsenal, New Jersey

                          Verdict: "GUILTY"

Student "worm" whiz is found guilty.  A U.S. court jury returned its verdict
about 9:30 pm after approximately six hours of deliberation.  Robert T. Morris
was found guilty of federal computer tampering charges for unleashing a rogue
program that crippled a nationwide computer network (Internet system).  A date
for sentencing has not yet been set.  Morris faces up to five years in prison
and a $250,000 fine.  He is the first person brought to trial under a 1986
federal computer fraud and abuse law that makes it a felony to break into a
federal computer network and prevent authorized use of the system.  Morris
testified that he had made a programming error that caused a computer "worm" to
go berserk and cripple the Internet system back on November 2, 1988.  The
"worm" he designed immobilized an estimated 6,000 computers linked to Internet,
including ones at the NASA, some military facilities and a few major
universities.  Morris's attorney Thomas Guidoboni argued that Morris never
intended to prevent authorized access.  However testimony showed Morris did
indeed deliberately steal computer passwords from hundreds of people so the
"worm" could break into as many computers as possible.  It was brought out in
the trial that he took deliberate and conscious steps to make the rogue program
difficult to detect and eliminate.  Morris camouflaged sending of the program
by unleashing it from the computer system at Massachusetts Institute of
Technology in Cambridge and made it look like it had been sent from the
University of California at Berkeley so authorship of the program could not be
traced to him at Cornell.  Other evidences showed Morris had at least six
earlier versions of the "worm", which had been found on his Cornell computer
accounts and that his own comments on the "worm" program used the words
"break-in" and "steal".

Advance Program for Oakland Symposium (REVISED, 9 Jan 90)

Debbie Cooper <>
Mon, 15 Jan 90 10:34:30 PST
    1990 IEEE Symposium on Research in Security and Privacy
            ADVANCE PROGRAM (Proceedings later from IEEE)
Monday, May 7, 1990

Praxis I, Steve Lipner, Chair
Status Update, Steve Lipner
A VMM Security Kernel for the VAX Architecture, Paul Karger, Mary Ellen
      Zurko, Douglas W. Bonin, Andrew H. Mason
An Architecture for Practical Delegation in a Distributed System, Morrie
      Gasser, Ellen McDermott
Practical Authentication for Distributed Computing, John Linn
SP3 Peer Entity Identification, Bill Birnbaum

Praxis II, Elizabeth Sullivan, Chair
The Army Secure Operating System, Neil Waldhart
Specification and Verification of the ASOS Kernel, Ben L. Di Vito,
      Paul H. Palmquist, Eric R. Anderson, Michael L. Johnston

Database I, Teresa Lunt, Chair
Integrating an Object-Oriented Data Model with Multilevel Security,
      Sushil Jajodia, Boris Kogan
A Little Knowledge Goes a Long Way: Fast Detection of Compromised Data
      in 2-D Tables, Dan Gusfield
Extending the Brewer-Nash Model to a Multilevel Context, Catherine Meadows

Database II, Earl Boebert, Chair
Polyinstantiation and Integrity in Multilevel Relations, Sushil Jajodia,
      Ravi Sandhu
Naming and Grouping Privileges to Simplify Security Management in Large
      Databases, Robert W. Baldwin
Referential Secrecy, Rae K. Burns

Tuesday, May 8, 1990

Information Flow, John Rushby, Chair
Information Flow in Nondeterministic Systems, J. Todd Wittbold, Dale M. Johnson
Constructively Using Noninterference to Analyze Systems, Todd Fine
Probabilistic Interference, James W. Gray, III
Security Models and Information Flow, John McLean

Access Control and Integrity, Roger Schell, Chair
Beyond the Pale of MAC and DAC — Defining New Forms of Access Control,
      Catherine Jensen McCollum, Judith R. Messing, LouAnna Notargiacomo
Some Conundrums Concerning Separation of Duty, Michael J. Nash, Keith R. Poland

Authentication, Tom Berson, Chair
The Role of Trust in Protected Mail, Martha Branstad, W. Curtis Barker,
      Pamela Cochrane
On the Formal Specification and Verification of a Multiparty
      Session Protocol, Pau-Chen Cheng, Virgil D. Gligor

Reasoning about Belief in Crytographic Protocols, Li Gong, Roger Needham,
      Raphael Yahalom
A Security Architecture and Mechanism for Data Confidentiality
      in TCP/IP Protocols, Raju Ramaswamy

Auditing and Intrusion Detection, Jim Anderson, Chair
The Auditing Facility for a VMM Security Kernel, Kenneth F. Seiden,
      Jeffrey P. Melanson
Adaptive Real-time Anomaly Detection Using Inductively Generated
      Sequential Patterns, Henry S. Teng, Kaihu Chen, Stephen C-Y Lu
Auditing the Use of Covert Storage Channels in Secure Systems, Shiuh-Pyng
      Shieh, Virgil D. Gligor

Wednesday, May 9, 1990

Verification, Deborah Cooper, Chair
The Deductive Theory Manager: A Knowledge Based System for Formal Verification,
      Ben Di Vito, Cristi Garvey, Davis Kwong, Alex Murray, Jane Solomon, AmyWu
Formal Construction of Provably Secure Systems with Cartesiana, Heinz
      Brix, Albert Dietl
Verifying A Hardware Security Architecture, Joshua D. Guttman, Hai-Ping Ko
A Hierarchical Methodology for Verifying Microprogrammed Microprocessors,
      Phillip Windley

Database III, Cristi Garvey, Chair
Transaction Processing in Multilevel-Secure Databases Using Replicated
      Architecture, Sushil Jajodia, Boris Kogan
Multiversion Concurrency Control for Multilevel Secure Database
      Systems, T.F. Keefe, W.T. Tsai
Modeling Security-Relevant Data Semantics, Gary W. Smith

Covert Channels Panel, Marv Schaefer, Chair
A1 With a Twist: Can a Fast Machine Be Secured?

Post-Symposium Panel Session, Carl Landwehr, Chair
International Orange II: A Spectrum of Computer Security Criteria

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