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RISKS-LIST: RISKS-FORUM Digest Monday 9 May 1988 Volume 6 : Issue 81

FORUM ON RISKS TO THE PUBLIC IN COMPUTERS AND RELATED SYSTEMS ACM Committee on Computers and Public Policy, Peter G. Neumann, moderator

Contents: Congress, computer breakdowns, and the SDI (Gary Chapman) Risks in timestamps (postmarks) (Alan Wexelblat) Risks in the phone system (Boyle) Risks of banking -- audio tellers (Daniel P Faigin, Alan M. Marcum) Military Aircraft Crashes in Germany (Michael Wagner, Michael Bednarek) KAL 007 (Steve Philipson) Atari ST virus hiding place (Allan Pratt) Viruses and write-protection (Fred Cohen, Bill Murray)

The RISKS Forum is moderated. Contributions should be relevant, sound, in good taste, objective, coherent, concise, nonrepetitious. Diversity is welcome. Contributions to RISKS@CSL.SRI.COM, Requests to RISKS-Request@CSL.SRI.COM. For Vol i issue j, ftp kl.sri.com, get stripe:<risks>risks-i.j ... . Volume summaries in (i, max j) = (1,46),(2,57),(3,92),(4,97),(5,85).

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Date: Mon, 9 May 88 11:02:30 PDT From: chapman@csli.stanford.edu (Gary Chapman) Subject: Congress, computer breakdowns, and the SDI

Last week while the House of Representatives was voting on a funding bill for the Strategic Defense Initiative, the House vote-tallying computer broke down. The computer reported a vote of 358 ayes and 237 nays on an amendment to kill the SDI program offered by Reps. Ron Dellums and Barbara Boxer. The House only has 435 members.

The irony was not lost on the opponents of the SDI. Nevertheless, the "manual" count of voice votes revealed defeat of the amendment 299-118.

-- Gary Chapman, Executive Director, CPSR

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Date: Mon, 9 May 88 09:48:50 CDT From: Alan Wexelblat <wex%sw.MCC.COM@MCC.COM> Subject: Risks in timestamps (postmarks)

PGN's note about the folks who used predated postmarks to cheat on the Superbowl contest reminded me of the following:

At <major post office> in <major city> where I used to live, it was a regular practice to stay open until midnight, April 15 to allow the filing of last-minute tax forms. These forms would be taken by postal employees at drive-up booths. One year, a housemate happened to notice that his form, dropped off at ~8 PM was stamped "11:59PM".

Apparently this was SOP - set the clocks to a fixed time and turn them off so they don't advance. Gives me lots of confidence in the accuracy of a postmark!

--Alan Wexelblat UUCP: {harvard, gatech, pyramid, &c.}!sally!im4u!milano!wex

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Date: Mon, 9 May 88 14:34:15 CDT From: boyle%antares@anl-mcs.arpa Subject: Risks in the phone system

A Mother's Day fire in an Illinois Bell switching center in Hinsdale has pointed up several RISKS resulting from evolution in the telephone system.

According to an Illinois Bell spokesman, "the switch seems to be alright", but the cables entering the office were severly damaged. Not surprisingly, phones in the area served by the office are completely out of service. However, my home phones, which are connected to a central office 5-6 miles from Hinsdale, are virtually out of service. I can call some local exchanges (those served by my switch), but I have no long distance service, no access to 611 repair service(!), no access to information, and no access to a human operator (dial 0). What is especially annoying is that attempting to use any of these services simply results in return to dial-tone, rather than a message indicating that there is a (known) problem. Estimated time to repair is variously quoted as three days to two weeks.

It seems to me that several recent trends have exacerbated this problem: Centralization of operator services (no operator at my central office, so calls to operator are routed over trunks). Ditto for 611 and 411. But, how to report phone service out of order when you can't get 611? Similarly, I can't call Ill. Bell, because all of their numbers are 1-800 ones, which evidentally must also be routed through the damaged trunk.

I also find it a startling RISK that my central office, which serves several exchanges, including Argonne National Laboratory, apparently has interoffice trunks to only one other central office. It would seem that for reasons of traffic balancing, if not redundancy, trunks to more than one other central office would be good practice.

Is anyone in the Bell system listening? Care to comment?

[I speak only for myself, as you guessed.]

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Date: Mon, 9 May 88 09:13:07 PDT From: faigin@sm.unisys.com (Daniel P Faigin) Subject: Risks of banking -- audio tellers (Re: RISKS-6.80, Ritchey Ruff) Organization: Unisys - System Development Group, Santa Monica

Our credit union also has an audio response system. I use it periodically, and tend to like it when I use it. There are a couple of additional comments I would like to make on top of what Ritchey has said.

For SSN-phobes, our system is worse. Our credit union uses SSNs as account numbers, and assigns you a random 4-digit PIN. I can see risks in this in response to line monitoring and playback threats.

However, the playback risks can only result in bounced checks. Note that access is limited to only your account, so money can only be moved between your accounts. If a check is requested, it is mailed ONLY to your address of record. The only risk there is that someone may intercept the mail. That's a wetware problem :-).

I did run into one problem with the system. According to federal law, transfers via systems like this are treated as telephone transfers. This limits you to 3 per month. One month, I exceeded this limit -- or at least I thought I did because the computer said it could not do the transaction because I had exceeded the number of transfers for the month. I didn't believe it when it happened, so I tried it again. It failed again. When I went to the credit union the next morning to see what had happened, it turned out that, even though I had gotten the error message, the computer had done the transfers.

Lastly, our system allows you to chain entry by using the * key. For example, to transfer money from subaccount 22 to subaccount 66, I can either enter the sequence ssn#pin#27#22#66#30000#1#99# and wait through all of the prompts, or enter, as a single action, ssn*pin*27*22*66*30000*1*99# I haven't yet had the courage to do everything at once. I typically use * to get me to the confirmation prompt. Daniel

W: UNiSYS/Defense Systems/System Development Group (nee SDC) 2400 Colorado Ave;Santa Monica CA 90406;213/829-7511x5162 (or 213/453-5162) H: 8333 Columbus Avenue #17; Sepulveda CA 91343 Email: (uucp) faigin@sdcrdcf.UUCP (arpa) faigin@SM.UNISYS.COM

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Date: 9 May 88 18:06:43 GMT From: marcum@sun.com (Alan M. Marcum) Subject: Risks of banking -- audio tellers (Re: RISKS-6.80, Ritchey Ruff) Organization: Sun Microsystems, Mountain View

The credit union to which I belong also has a touch-tone telephone banking service. When I signed up for it, they asked me to specify my "password" (four digits). Better than defaulting to something from my SSN (and our state doesn't even use them for drivers licenses).

This system allows you to transfer funds between sub-accounts within your account (sub-accounts are, for example, savings, checking, and loans). There is no provision for transferring funds to anything outside your account, nor a provision for requesting a check be issued. Had these facilities been provided, I would not have enrolled in the service, because of the risk involved.

Alan M. Marcum Sun Microsystems, Technical Consulting marcum@nescorna.Sun.COM Mountain View, California

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Date: Mon, 09 May 88 12:21 From: Michael Wagner new! +49 228 8199645 <WAGNER%DBNGMD21.BITNET> Subject: Military Aircraft Crashes in Germany (Henry Spencer)

In RISKS 6.79, Henry Spencer, after quoting my original article, says: > nuclear-reactor containment buildings are deliberately designed to > survive a direct hit from a crashing airliner (not as fast as a > military jet, in general, but much, much heavier).

I didn't mention this in my original posting, but shortly after the crash near the nuclear reactor, the interior minister got on the radio and told everyone roughly the same thing. I suppose this was meant to be reassuring, but it doesn't seem to have succeeded. All of these low-level flights are over populated areas (there are no un- or sparsely- populated areas in this part of Germany!), and the residents are scared. There is now a debate going on as to whether such low-level flights will be tolerated any more.

To try to put this in perspective, a plane crashed into a McDonalds in Munich about a year ago, so planes falling out of the sky on people's heads is currently a hot topic here. An article in "Der Speigel" a while ago talked about crowding in the air. It made the air over O'Hare sound like a Sunday stroll in the park. Particularly interesting, in light of this discussion, was the difference in air patterns that the militarily-proscribed airzones made.

Michael

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From: munnari!murdu.oz.au!u3369429@uunet.UU.NET (Michael Bednarek) Subject: Re: Military Aircraft Crashes in Germany (RISKS-6.79) Date: 9 May 88 02:11:38 GMT Organization: I.A.E.S.R., Melbourne University

>> In all, 35 military aircraft have fallen out of the skies here since 1960.

That number (35) is definitely wrong. I lived until 1983 in Germany, and by that time more than 120 crashes were reported. Mostly Starfighters.

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Date: Mon, 9 May 88 12:42:03 PDT From: Steve Philipson <steve@ames-aurora.arpa> Subject: KAL007 - the deafening noise continues (RISKS-6.79)

In RISKS-6.79 Clifford Johnson <GA.CJJ@forsythe.stanford.edu> writes:

> .... I think that PGN's tentative > suggestion that the matter might still be incompletely unravelled simply > cannot be denied - at least until a public inquiry is instigated.

Almost assuredly the matter is "incompletely unravelled [sic]", but it is also certain to remain that way, public inquiry or no. Such investigations are notorious for their failure to find facts and establish definitive chains of events. Take for example the Lindbergh kidnapping, Sacco and Vanzetti, J F Kennedy's assassination, or the current Contragate investigations. Such public inquiries have often resulted in the wrong answers being "found", or no answers at all. If answers do come out, they emerge many years later, after responsible parties are out of public office or deceased. Even then, such revelations are questionable as verification remains difficult.

The discussion over the nature of the course deviation is, at best, academic. We cannot prevent deliberate course deviations. However, we have identified several possible ways for such a deviation to occur unintentionally. What we should and are concerning ourselves with is how to prevent such errors in the future, and to establish systems and procedures that will prevent loss of life and property should other errors occur.

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Date: Mon, 9 May 88 10:14:26 pdt From: ucbcad!ames!atari!apratt@ucbvax.Berkeley.EDU (Allan Pratt) Subject: Atari ST virus hiding place

A perfect hiding place for viruses on the Atari ST has come to my attention. The reason it's interesting is it is a place where a VERY LARGE virus can live -- much larger than just the boot sector of a floppy.

The hole exists because the ST formats floppies with five-sector FATs (File Allocation Tables) even though at most three sectors will be used. Since there are two FATs per disk, this leaves four sectors for the virus. A boot-sector virus could be five sectors in length without impacting the user-visible free space on the disk.

The sectors in question are logical sectors 4, 5, 9, and 10 (where the boot sector is sector 0). These sectors are always zeroed by the built-in formatter (I can't speak for others). The rationale, I believe, for the five-sector FATs is so the root directory of the volume will appear on Side 1 of a double-sided disk, so a single-sided drive will not be fooled into thinking it can work with the disk.

I asked PGN about posting this -- about the tradeoff between warning the friendlies and informing the hostiles about this hiding place. As PGN pointed out, "... the underground will find out anyway. The crackers are networked better than everyone else."

So here is my posting. The cure for an infected disk is to make the boot sector non-bootable, and zero the four sectors listed above.

Opinions expressed above do not necessarily -- Allan Pratt, Atari Corp. reflect those of Atari Corp. or anyone else. ...ames!atari!apratt

[By the way, there is tons of stuff on VIRUS-L that is not appearing in RISKS. For those of you with a burning interest in viruses, please join VIRUS-L, as indicated in RISKS-6.75. PGN]

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Return-Path: <pyramid!uccba!ucqais!fc@unix.SRI.COM> Received: from unix.SRI.COM by KL.SRI.COM with TCP; Mon 9 May 88 00:45:19-PDT [From: fc@ucqais.uc.edu (Fred Cohen)???] Subject: Viruses and write-protection [RISKS-6.79]

[I MUST ASSUME THIS MESSAGE IS FROM FRED COHEN, EVEN THOUGH HIS MAILER DID NOT INCLUDE HIS "FROM:" AND "DATE" FIELDS, USING INSTEAD THE "DATE:" AND "FROM:" FIELD FROM THE MESSAGE TO WHICH HE WAS RESPONDING, AS FOLLOWS: Date: Thu May 5 16:40:20 1988 CDT From: Dennis Director <dennis%molly.uucp@eecs.nwu.edu> Subject: Viruses and write-protection CURIOUS. PGN]

[From: Dennis Director <dennis%molly.uucp@eecs.nwu.edu>] >I have an XT-compatible computer with DOS 3.2 and all of its utilities and >programs in the write-protected portion of the hard disk. I invite both Dr. >Fred Cohen of the University of Cincinnati and William Murray to come to my >office ... I am (100%) sure that none of these programs will >modify my boot block, my partition table, the operating system files or any of >the DOS programs (.COM or .EXE) stored on my hard disk, which will be hardware >write-protected.

What makes you think all viruses do only this?

>A scratch area of the hard disk will be writeable at all >times. Simply copying a Trojan Horse into the scratch section of the disk, >should obviously not be considered "infecting my system".

Copying a "Trojan Horse" onto your system would not constitute infecting it even if it were in your operating system. Since you don't seem to know what a virus, I would suggest that you purchase a copy of my dissertation for a more formal definition. (sending me $20 will buy it).

I assume from your comment that it would however be considered "infecting your system" if we wrote a virus that infected source programs in your "scratch" area. If they then infected floppies and other information, this would also be infection, and if when you finally did write enable your hardware protected disk to put in another "protected" piece of software, the virus spread into that area, that would also be considered infecting your system.

> Since Dr. Cohen has stated that "you cannot write protect >lotus, etc because of copy protection" we will also have a copy of Lotus >123 installed and working in the write-protected section, as we have had >for almost two years.

Lotus disks that I have seen at a number of sites have had this property, that is not to say that it is impossible to make them work that way. We contacted Lotus to have them make available a version with this property, and they refused. I did not say that for all lotus implementations, write protection was not possible, only that we (and you if you were in the set of people with the versions of lotus we were using) could not write protect them and have them work in the systems that we were working with. If lotus has backed off of this policy, I would only be happy to hear about it, but since your copy is so old, it may be that a recent change in their policy has made this impossible for newer versions.

> This will be a fully legitimate copy-protected > installed version of 123. It runs perfectly from the write-protected > zone and cannot be infected.

Neither Bill Murray nor I has ever said that you can modify information that is physically write protected, and I doubt if either of us ever would. What we said is that it is only safe if it is 100% protected 100% of the time. Since you have already admitted that it would be possible to infect the writable part of your hard disk, I assume that you in fact agree with us.

On the other hand, you should agree that you do not know for certain if there is or is not an infected program on the write protected segment of your hard disk, and that when you install software on this part of your disk, it is entirely possible that without special precautions, you could infect one of those temporarily write enabled files. Furthermore, I am not convinced by your statement of belief that your disk is in fact write protected in hardware. I have seen many people who believed such things become unpleasantly surprised.

> Why go on debating that which can be simply demonstrated? Seems > like a fair offer to me!

In many cases, it cannot be demonstrated that it is impossible to do something simply by trying to do it. If you study the philosophy of science (see a famous work by Karl Popper), you will find that "FOR ALL" statemewnts covering infinite sets cannot be verified by finite numbers of supporting examples. They can however be refuted by a single example. If we succeeded in infecting your system, it would prove you wrong, but by failing to do so, it does not prove you right.

Also, it is customary when proclaiming perfection (even with the various nebulous "except"s here and there) to make it worthwhile to demonstrate counter examples. I would suggest that in making such a challenge, you offer a $100,000 bet, so that if we decide to take you on, it will be worth our time to take you down, and so that if we take you on and fail to take you down, you will be able to have a very nice meal in your new home.

Fred Cohen

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Date: Mon, 9 May 88 12:34 EDT From: WHMurray@DOCKMASTER.ARPA Subject: D. Director: "Enough is enough."

Dennis Director and I agree on the following: enough is enough.

However, Director seems to believe that somewhere, both F. Cohen and I, have asserted that write protection is not sufficient for protecting an operating system from infection by a virus. We have not. Indeed, we have both conceded that 100% protection of a hard disk 100% of the time results in 100% protection of the hard disk from infection. That I have so conceded is a matter of record. That I have ever asserted otherwise is not a matter of record. If it were, I am sure that Director would cite it.

Therefore, Director's challenge to me to prove that which I have never asserted, can justly be construed as disingenuous.

What I have said, and will continue to say until I begin to get feedback that the message is being heard, is that making one, or even many, machines immune to infection is not sufficient to prevent the spread of the virus.

Director insists upon seeing the "protection of the operating system and other commonly used programs" as the issue. I do not blame him; if I were in the business of selling write protection, I suspect that I would see it that way too.

Nonetheless, I will continue to assert that it is the SPREAD OF THE VIRUS, rather than the protection of one or more systems, that is the issue.

I must confess to a great deal of disappointment that all of the response to my review of Director's product has focused on assertions that I have been extremely cautious not to make and has been totally silent on those that I have gone to such great pains to make. I feel much as George Washington must have felt when writing to the Continental Congress: "Is anybody there?"

William Hugh Murray, Fellow, Information System Security, Ernst & Whinney 2000 National City Center Cleveland, Ohio 44114 21 Locust Avenue, Suite 2D, New Canaan, Connecticut 06840

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End of RISKS-FORUM Digest ************************