The RISKS Digest
Volume 17 Issue 50

Saturday, 2nd December 1995

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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o Montgomery County, PA, experience with new voting machines
Leonard Finegold
o Sex, Lies and Backup Disks
Peter Wayner
o French civil servants paid twice
Pierre Lescanne
o Risk of gradual failure
Stuart Staniford-Chen
o AT&T Code Policies. Hmmmm...
Pete McVay
o More on alarms and alarm silencing
Cliff Sojourner
o Re: risks in medical equipment
Bill Harvey
o Re: Is chip theft high-tech crime?
Jacob Kornerup
o Error Checking ('NEW should never abort!' and 'Writing solid code')
Randy Gellens
o More Microsoft Word Spelling RISKS
Eli Goldberg
o Re: Spelling Correctors
Alek O. Komarnitsky
o Re: Apple spellchecker
David Silbey
o Re: Spell-checking
Martin Minow
o Re: Spelling Correctors Self-Applied? Not in Microsoft Word
E Foley
o Re: Another Oakland airport radar outage (Risks from the Future?)
o ABRIDGED info on RISKS (comp.risks)

Montgomery County, PA, experience with new voting machines

"Peter G. Neumann" <>
Fri, 1 Dec 95 17:07:11 PST

Leonard X. Finegold of the Physics Department at Drexel University sent me issues of the West section of the Philadelphia Inquirer for the two Thursdays (9 and 16 Nov 1995, p.W1 in each case) immediately following the November 1995 election day. I have distilled two long articles.

Pennsylvania's Montgomery County spent $3.8 million on new MicroVote voting machines, and attempted to use them in a very-low-turnout off-year election on 7 Nov 1995. Unfortunately, things did not go as planned. There were massive voting-machine breakdowns, 150 service calls, long delays in repairs, and phantom vote tallies (for example, 22,000 write-ins were recorded for prothonotary). There were some three-hour waiting lines to vote, and many people left without voting. Incomplete results were wildly erroneous, suggesting the wrong candidate was winning. Although test runs had been successful, something about the county's cross-filed candidates seems to have caused the software to fail unanticipatedly. By 4am, the apparently bogus write-in votes had vanished altogether. When the smoke finally cleared, the official results were apparently satisfactory — and unchallenged. It was also a major gremlin-style event: printers, copiers, elevators, even radios used by the repair crews failed. (The MicroVote system reportedly has been used successfully in counties in Kansas, North Carolina, and Indiana.)

Sex, Lies and Backup Disks

Peter Wayner <>
Fri, 1 Dec 1995 15:23:13 -0500

An article in the 1 Dec 1995 *Wall Street Journal* (pg A14) should serve as a stark reminder why people should make sure to overwrite their disks when they delete files. Jean Lewis is someone from the government who has made some noise about something illegal connected with the Clinton administration. (Details are too confusing for this short venue.) She's apparently a Republican star witness. The Democrats apparently were given a computer disk with important files on them. Unbeknownst to Ms. Lewis and the Republicans, the disk also contained the text of a letter she wrote a friend about her stepson. In the letter she compares him to Bill Clinton, whom she calls a "lying bastard" for denying he slept with Gennifer Flowers.

The article says that Lewis had deleted the file long before she handed over the disk containing other files to the Democrats. Richard Ben-Veniste, a lawyer for the Democrats, pulled out a copy of the letter during the hearing and quoted the "lying bastard" phrase as proof that she was only on a political vendetta when she uncovered her charges. Here's the article's quote of Ben-Veniste:

Apparently you didn't think it was on the disk but it was. That's the funny thing about these disks. I don't understand how they do it, but they can find the stuff on the disk that nobody thinks is there. I hate it when that happens, but here it is, Ms. Lewis.

What a town! They spend their waking hours trying to find out what other people think of them. Then they get upset when it's not good. The moral: investigate disk erasure programs that overwrite the disk a sufficient number of times.

[Also reported by Bill McGeehan <IRMTAQA2@SIVM.SI.EDU>.]

French civil servants paid twice

Pierre Lescanne <>
Thu, 30 Nov 1995 10:45:37 +0100

Due to a computer mistake of Banque de France, civil servants and other people paid by the French State were paid twice for the month of November 1995. Apparently some others were paid not at all.

Pierre Lescanne

Risk of gradual failure

Stuart Staniford-Chen <>
Fri, 1 Dec 95 15:15:54 PST

I wanted to record a small risk here for posterity. My workstation contains a Pentium chip. Since this chip generates so much heat, the motherboard design incorporates a small (1W) cooling fan which sits immediately atop the chip heat-sink. This is in addition to the usual power-supply cooling fan contained in most workstations.

Sometime in the last month or two, this small chip-cooling fan died. The only reason that this might be of wider interest is the symptoms this caused in the computer. What happened is that, over a period of weeks, the machine became "flaky". Early symptoms were occasional difficulty logging in or launching applications. Later on, I experienced strange events such as compiler error messages complaining of non-existent instructions. These would go away if I attempted the compilation again. Towards the end, cutting and pasting between windows became unreliable (what was pasted would differ in a few characters from what was cut).

For a long time, the machine was basically usable despite these integrity problems - usable enough that I remained in denial about the need to take time to investigate further. The problems were initially rare, and became more and more frequent over time. It was easy at first to put the problem down to software (though the lack of repeatability should have been a clue). Finally, the situation became severe enough that I opened the box and immediately found the burnt out fan. I am guessing that the fan became clogged with dust and gradually got less effective before dying altogether. This would explain the slow worsening of symptoms.

The point is that the machine never gave any diagnostic, and never failed in any repeatable or well-defined way. It just gradually became less and less deterministic in its operation. The risks of this are obvious, I think.

Stuart Staniford-Chen, Dept of Computer Science, UC Davis, CA 95616 w:(916) 754-8742

AT&T Code Policies. Hmmmm...

Pete McVay <>
Tue, 28 Nov 95 18:16:18 PST

I recently lost my AT&T phone credit card, so I applied to them for a replacement. I was informed that they would have to change the PIN (four-digit access code appended to my phone number on the card) and would issue me a new one. I received the new card, with the new PIN, about a week ago, and tried to use it today. It kept rejecting the number as invalid.

I called AT&T, and because I was near the phone I use for billing, the help desk assistant was able to confirm that it was me. She tried my card and my new PIN, and it didn't work. She then gave me the PIN that worked--my old one, which was supposedly replaced. She was in a very talkative mood, and explained that this happened to her quite often. If a PIN is changed, in her experience, she had to wait at least a day before putting in the new PIN, or it wouldn't take. I can think of a number of reasons for this little bug, since their database is huge and distributed. But that's not the point here...

The help desk person said she has had this problem for at least six months, and even though she has complained up the line, the waiting bug persists. This waiting period also isn't documented, so inexperienced personnel tend to make the mistake over and over, leading to many calls to her desk.

I'm not familiar enough with AT&T software methods to comment extensively on the whys and hows of their coding policies, but it would seem to me that their attitude to this (minor) bug is disturbing. The bug is obviously a serious problem to customers, and is also easily fixed in a distributed database environment. At the very least, a lockout would prevent new codes from being entered for 24 hours. If their approach to this bug is in any way indicative of their general policies, then I really wonder about the stability of the rest of their code, and I see some of the well-publicized phone outages "due to software bugs" in a new light.

more on alarms and alarm silencing

30 Nov 95 14:09:00 -0800

John Strohm's article about the risks of ignoring medical alarms in RISKS-17.49 struck a nerve.

We had a similar experience. Our newborn had to spend a few days in the Newborn Intensive Care Unit (NICU).

All patients (babies) in the NICU are wired up with four sensors: heart rate, breath rate, temperature, and blood O2 level. The heart rate and breath rate sensors were particularly unreliable, intermittently getting good data and noisy data and no data.

The data monitors were configured to sound an alarm and flash the display when any of the sensors was reading data out-of-range. So far so good: an alarm indicates potential trouble.

Problem is, the data from the sensors was so unreliable that the monitors' alarms were always going off. In fact, the entire 20-bed NICU was always noisy with various alarms (patient monitors, IV pumps, etc.) going off.

What troubled me most was the NICU staff's response to the monitor and IV pump alarms: ignore them! When the staff's rounds brought them to the patient then they would press the "alarm-silence" button.

No one at the NICU had a good answer for me when I asked "why have audible alarms if you always ignore them?"

The risk here is that a real life-threatening situation would not be discovered in time to help the patient. The usual caveats about over-reliance on technology also apply.

Cliff Sojourner

Re: risks in medical equipment

Thu, 30 Nov 1995 09:45:37 0000

John R Strohm's account of problems with morphine-delivery pumps in hospitals shows the problems associated with alarms. But there's an underlying issue.

My mother-in-law was recently hospitalised with what turned out to be severe dehydration. She was put on an active (pumped) drip system. When we were visiting, a young doctor made some adjustments to the controls, then left the room. I noticed that the flow rate was now showing zero. When I queried this with a nurse, we were told that "the doctor has adjusted the rate". We pointed out that a dehydrated patient presumably should be getting some fluid intake, but to no effect. After about five minutes, another doctor passed by. When we spoke to him, he agreed with us and pressed the "start" button on the pump.

Part of health service culture is that young doctors often make mistakes, and experienced nurses can often fix their mistakes informally. I have seen this happen when I've been a patient. But not in this case. I suspect the difference is that this case concerned technology. I don't think the nurse was very sure what the displays and the controls meant. Is this just a question of training?

I'm reminded of studies which show that women are more intimidated by digital technology than men. Not because of intelligence or ability, but because some technologies are socially defined as 'male' - video recorders and TV remotes being good examples, as well as computers. In the hospital context, I suspect technology is perceived as something *other* than normal nursing care. It is owned by someone else. The other possible explanation is that nurses are reluctant to question the authority of doctors, even if (to a lay observer) the doctor has clearly made a mistake. Neither explanation is very comforting.

Bill Harvey, Quality Assessment Branch, Scottish Higher Education Funding Council Tel: 0131 313 6513 Fax: 0131 313 6501

Re: Is chip theft high-tech crime? (Rosenthal, RISKS-17.49)

Jacob Kornerup <>
Thu, 30 Nov 1995 11:41:43 -0600

You are right on the semantics of "High-Tech" crime. The difference between the food flavoring and RAM chips is that once stolen RAM chips are easy to transport (how many K$ worth do you think fits into a suitcase ?) and they are easy to sell because there is a large number of costumers for them. There are even shops these days that sell "Grey Market" RAM chips, that is chips that have uncertain origins. While most of these are legitimate, it can be very difficult to assert the legitimacy of chips that are being offered.

The term "High-Tech" comes from the Police Departments. Austin, Texas has such a division that deals with everything from stolen RAM chips over software piracy to hacker break-ins. It takes an investment of resources to train police officers in the area of computers (this includes such mundane issues as the current price of hardware) and it is a trade-off which crimes to pursue. From a meeting with member of our local High Tech Crime Unit I attended, it was clear that they would focus on the cases that had public exposure. That is an armed robbery for chips or hard drives would get serious attention, small scale piracy would not. They would spend time on the internet looking for what looked like thieves trying to unload stolen goods.

As for the "True High Tech" crimes such as intrusion they did tells us that they would help the companies who had been victimized by investigating the crime, but would not give us too many details. It was pretty clear that the officers were not computer experts, but rather police officers exploring new grounds.

The disturbing thing was that the local police officers could not get any help from the FBI, apparently the FBI does not have a "High-Tech" crime unit or at least not one that will cooperate with local authorities. The only cooperation the local police could get was from similar units in other "High Tech" cities like San Jose and Portland. Given the non-local nature of "net-crime" this is disturbing.

Jacob Kornerup ( Department of Computer Sciences
University of Texas, Austin

Error Checking ('NEW should never abort!' and 'Writing solid code')

29 NOV 95 21:19

In Risks 17:48, David Chase <> wrote:

> So, I ask, those of you theorizing so confidently about code which
> recovers from errors, have you written such code? Have you tested it
> thoroughly? Do you have confidence that the OS code to handle this
> situation was tested thoroughly? (If so, why? Do you think people
> write and run this sort of code every day? It's not exactly as common
> as opening and closing files.)

In my experience (with Unisys A Series systems), programs (both vendor supplied and user written) make heavy use of error recovery facilities. If this stuff breaks, we would know about it right away. There are also test suites for the OS error recovery facilities.

Of course, these systems handle errors and error recovery differently from most. That's one of the reasons they are so much fun to use.

As best I could make out, David was talking about stack overflow conditions. On the A Series, as long as there is an error handler statement at a safe place (that is, not at the top of an already overflowed stack), if a stack overflow happens, the stack is cut back, and control passes to the error handling statement. (The program can get a hidden stack overflow, but the OS will just stretch the stack for it. Only if the stack can't be stretched will an actual stack overflow condition exist.)

In Risks 17:48, (Edward Reid) wrote:

> Security, in the broad sense, is a joint responsibility of the
> compilers, the instruction set architecture (ISA), and the operating
> system (MCP). The compilers do not generate code which
> unconditionally violates security, but often the generated code is
> further checked by the ISA or the MCP. For example, the ISA checks
> array bounds and prevents the code from accessing memory outside that
> allocated to the task. The MCP manages file access security.

The A Series systems can best be thought of as object-oriented at the hardware level. Tasks (threads, stacks, processes), files, arrays, etc. are all objects. The compilers won't let you perform an improper action on an object. At a lower level, the hardware ensures that the operator and the operand match. (Can't do a normal store onto a pointer, for example). Programs can't access memory per se. They can only access objects (scalers, arrays, files, tasks, etc.) A lot of the bugs people fight with on other systems just aren't an issue.

In Risks 17:48, (Thomas Lawrence) wrote:

> In my own experience, there are a great many assertions which are
> unacceptably expensive to check.

Many of the examples cited aren't more expensive on the A Series, for reasons previously noted. For example, if I declare a data structure or object in a procedure, the compiler flags the block, and the when the block is exited, the hardware calls the OS to deallocate the objects.

> Perhaps the best solution is to give 2 versions of the program to the
> end user. One with debugging.... The other without.... Then let the
> user decide which to use.

Most A Series system software in fact comes in two flavors: regular and diagnostics. The latter typically includes many extra validity checks, and trace functions.

Randall Gellens Mail Stop MV 237 (714) 380-6350

More Microsoft Word Spelling RISKS

Eli Goldberg <>
Thu, 30 Nov 95 09:29:43 -0500

Peter Neumann's story about the Word spelling checker glitches brought back memories of Microsoft's sales presentation for the (then new) Office 4.2 to the chemical company that I interned at last summer.

Imagine over two hundred employees packed into an auditorium, with a Microsoft employee at the front excitedly running through his "gee-whiz-bang" software presentation of the virtues of the new Microsoft Office.

The salesman started to demonstrate the "Autocorrect" feature in Word, which automatically fixes the most common typos as soon as users make them. It also includes a feature allowing users to add their most common typos to the list.

To demonstrate this, the presenter deliberately misspelled a word. As I recall, he mistyped "Personal Memo" as "Porsenal Memo".

The computer naturally flagged it as a typo. Good so far. To show Word easily fixes such common typos, the salesman activated the "Autocorrect" function to fix it.

Unfortunately, he entered "Personall" as the automatic correction that Word should now use for "Personal"! OOPS. Wrong spelling. But no problem. Word gladly accepted it anyway.

He then proceeded to unintentionally demonstrate how Word can now automatically add typos to all of his "Personall Memos".

After he concluded this segment of the presentation by proclaiming the brilliance of the programmer's designers and asking us, "What do you Office a work of magic?", I nearly fell over laughing in my chair.

In short, Microsoft's design implicitly assumed that users would be able to spell words correctly in order to use their spell checker. I suspect that this may have been a questionable assumption. But a damned funny sales presentation. ;)

Eli Goldberg Turner Broadcasting, QA Engineer

Re: Spelling Correctors (RISKS-17.49)

Alek O. Komarnitsky <>
Thu, 30 Nov 95 00:27:46 MST

The classic example (IMHO) is FrameMaker ... which flags the word "Interleaf" and recommends you change it to "FrameMaker".

Yes, there is a "risk" there ... but I personally appreciate the programmers who had a sense of humour here! ;-)

P.S. I don't know if this is true in the latest 5.0 version.

Re: Apple spellchecker

David Silbey <>
Thu, 30 Nov 1995 14:52:58 +0100
  1. Macintosh, not MacIntosh.
  2. I wasn't aware that Apple made a spellchecker; an OS certainly, and computers, of course, but the only spellcheckers I can think of would be the ones made by Claris, which is an independent subsidiary of Apple. A picked nit, almost certainly.
  3. 'Laserwriter' _is_ an Apple product, while 'Laserjet' is from Hewlett-Packard.
David J Silbey Duke University
[Noted by (Elliot Wilen), (Robert Dorsett), and "Barrett P. Eynon" <barry@playfair.Stanford.EDU>, among others. Scott said correctly that the Laserwriter is an Apple product — I goofed in placing the parenthetical. For the record, his observation was that a product on an Macintosh system suggested the nonApple alternative. PGN]

re: Spell-checking (RISKS-17.49)

Martin Minow <>
Thu, 30 Nov 1995 09:53:03 +0100

The spell checker on ClarisWorks 4.0 accepted the following sentence from Scott Siege's item in Risks 17.32:

The ... spellchecker suggested changing "Laserwriter" to "Laserjet".

It offered the following suggestions:

spellchecker -> spell checker
Laserwriter -> LaserWriter
Laserjet -> LaserJet

All of these seem reasonable to me.

Martin Minow
[Good. Things are improving. PGN]

Re: Spelling Correctors Self-Applied? Not in Microsoft Word

Thu, 30 Nov 1995 10:43:26 -0400

Allow me to point out that the Word spellchecker is actually a third-party plug-in, which Microsoft buys from a well-known publisher of digital reference materials. As with any good dictionary, the Word spellcheck module does not incorporate words until they can be considered by the editors to have become a part of the language. When Microsoft purchased this product, probably in late 1993, most of these words were not part of the language or did not have the currency they do today.

The Risks of such language databases are already well-mitigated, in my opinion, by the capacity of Word and similar programs to add words to the spellcheck database. They could be mitigated further by Microsoft offering updates to the dictionary, perhaps for download on its website, but with the feature of user customization, who would bother to do this? Would you?

I'm not a Microsoft apologist, but this is less a Risk than a potshot at a popular target.

Re: Another Oakland airport radar outage (Risks from the Future?)

"Peter G. Neumann" <>
Thu, 30 Nov 95 8:42:25 PST

There was a persistent iterative off-by-one error in the three dates mentioned yesterday in RISKS-17.49. I made the following corrections in the archive copy at FTP.SRI.COM.

The correct dates were simply one day earlier:

>The Oakland airport radar failed again on 28 Nov 1995 for about two hours,

>... There had also been a brief failure on 27 Nov 1995, ...

>[Source: *San Francisco Chronicle*, 29 Nov 1995, A13.

Julian Elischer <> noted the glitch and wondered if he could have had the stock market pages or race results from the 30 Nov paper on 29 Nov.

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