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RISKS-LIST: RISKS-FORUM Digest Monday, 7 December 1987 Volume 5 : Issue 71

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

Contents: The Amiga VIRUS (by Bill Koester) (Bernie Cosell) Radar's Growing Vulnerability (PGN) Computerized vote counting (Lance J. Hoffman) United Airlines O'Hare Sabotage? (Chuck Weinstock) Re: Whistle-blowers who (allegedly) aren't (Jeffrey Mogul) In Decent Alarm (Bruce N. Baker) Need for first-person anonymous reporting systems (Eugene Miya) Apollo 11 computer problems (Michael MacKenzie) Interconnected ATM networks (Win Treese) Can you sue an expert system? (Gary Chapman, Jerry Leichter, Bruce Hamilton) What this country needs is a good nickel chroot (Bob English)

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 SRI.COM, CD STRIPE:<RISKS>, GET RISKS-i.j. Volume summaries for each i in max j: (i,j) = (1,46),(2,57),(3,92),(4,97).

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Date: Mon, 7 Dec 87 0:25:23 EST From: Bernie Cosell <cosell@WILMA.BBN.COM> To: risks@csl.sri.com Subject: The Amiga VIRUS (by Bill Koester)

From: bill@cbmvax.UUCP (Bill Koester CATS) Newsgroups: comp.sys.amiga Subject: Amiga VIRUS Date: 13 Nov 87 19:32:05 GMT Organization: Commodore Technology, West Chester, PA

THE AMIGA VIRUS - Bill Koester (CATS)

When I first got a copy of the Amiga VIRUS I was interested to see how such a program worked. I dissassembled the code to a disk file and hand commented it. This article will try to pass on some of the things I have learned through my efforts.

1) Definition. 2) Dangers. 3) Mechanics 4) Prevention

1. - Definition.

The Amiga VIRUS is simply a modification of the boot block of an existing DOS boot disk. Any disk that can be used to boot the Amiga (ie workbench) has a reserved area called the boot block. On an Amiga floppy the bootblock consists of the first two sectors on the disk. Each sector is 512 bytes long so the boot block contains 1024 bytes. When KickStart is bringing up the system the disk in drive 0 is checked to see if it is a valid DOS boot disk. If it is, the first two sectors on the disk are loaded into memory and executed. The boot block normally contains a small bit of code that loads and initializes the DOS. If not for this BOOT CODE you would never see the initial CLI. The normal BOOT CODE is very small and does nothing but call the DOS initialization. Therefore, on a normal DOS boot disk there is plenty of room left unused in the BOOT BLOCK.

The VIRUS is a replacement for the normal DOS BOOT CODE. In addition to performing the normal DOS startup the VIRUS contains code for displaying the VIRUS message and infecting other disks. Once the machine is booted from an infected disk the VIRUS remains in memory even after a warm start. Once the VIRUS is memory resident the warm start routine is affected, instead of going through the normal startup the VIRUS checks the boot disk in drive 0 for itself. If the VIRUS in memory sees that the boot block is not infected it copies itself into the boot block overwriting any code that was there before. It is in this manner that the VIRUS propagates from one disk to another. After a certain number of disks have been infected the VIRUS will print a message telling you that Something wonderful has happened.

2. - Dangers.

When the VIRUS infects a disk the existing boot block is overwritten. Since some commercial software packages and especially games store special information in the boot block the VIRUS could damage these disks. When the boot block is written with the VIRUS, any special information is lost forever. If it was your only copy of the game then you are out of luck and probably quite angry!!

3. - Mechanics.

Here is a more detailed description of what the virus does. This is intended to be used for learning and understanding ONLY!! It is not the authors intention that this description be used to create any new strains of the VIRUS. What may have once been an innocent hack has turned into a destructive pain in the #$@ for many people. Lets not make it any worse!!

a.) Infiltration.

This is the first stage of viral infection. The machine is brought up normally by reading the boot block into memory. When control is transferred to the boot block code, the virus code immediately copies the entire boot block to $7EC00, it then JSR's to the copied code to wedge into the CoolCapture vector. Once wedged in, control returns to the loaded boot block which performs the normal dos initialization. Control is then returned to the system.

b.) Hiding Out.

At this point the system CoolCapture vector has been replaced and points to code within the virus. When control is routed through the CoolCapture vector the virus first checks for the left mouse button, if it is down the virus clears the CoolCapture wedge and returns to the system. If the left mouse button is not pressed the virus replaces the DoIO code with its own version of DoIO and returns to the system.

c.) Spreading.

The code so far has been concerned only with making sure that at any given time the DoIO vector points to virus code. This is where the real action takes place. On every call to DoIO the virus checks the io_Length field of the IOB if this length is equal to 1024 bytes then it could possibly be a request to read the boot block. If the io_Data field and A4 point to the same address then we know we are in the strap code and this is a boot block read request. If this is not a boot block read the normal DoIO vector is executed as if the virus was not installed. If we are reading the boot block we JSR to the old DoIO code to read the boot block and then control returns to us. After reading, the checksum for the virus boot block is compared to the checksum for the block just read in. If they are equal this disk is already infected so just return. If they are not equal a counter is incremented and the copy of the virus at $7EC00 is written to the boot block on the disk. If the counter ANDed with is equal to 0 then a rastport and bitmap are constructed and the message is displayed.

d.) Ha Ha.

< Something wonderful has happened > < Your AMIGA is alive!!! > < and even better > < Some of your disks are infected by a VIRUS > < Another masterpiece of the Mega-Mighty SCA >

4. - Prevention.

How do you protect yourself from the virus?

1) Never warm start the machine, always power down first. (works but not to practical!)

2) Always hold down the left mouse button when rebooting. (Also works, but only because the VIRUS code checks for this special case. Future VIRUS's may not!)

3) Obtain a copy of VCheck1.1 and check all disks before use. If any new virus's appear this program will be updated and released into the public domain. VCheck1.1 was posted to usnet and will also be posted to BIX. ( Just like the real thing the best course of action is education and prevention!)

Bill Koester -- CBM >>Amiga Technical Support<< UUCP ...{allegra|burdvax|rutgers|ihnp4}!cbmvax!bill PHONE (215) 431-9355

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Date: Mon 7 Dec 87 13:52:21-PST From: Peter G. Neumann <NEUMANN@csl.sri.com> Subject: Radar's Growing Vulnerability To: RISKS@KL.SRI.COM

For readers of SCIENCE, the 27 November 1987 issue (p. 1219) has a nice article by Stephen Budiansky (titled asa the Subject line above) on the problems of defensive radars. ``As weapons become smarter, they learn to "see" radar beams as pathways to their target, gaining an advantage over defensive systems.'' The caption on a picture of the smoking HMS Sheffield says that it ``was hit in the Falkland Islands war in 1982 when its radars attracted a rocket launched from a fighter plane 20 miles way.'' (RISKS readers will recall that the British investigation concluded that the Sheffield's own radars were jammed by a communcation back to London that was being held at the time.)

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Date: Mon, 7 Dec 1987 14:22 EST From: Lance J. Hoffman <LANCE%GWUVM.BITNET@WISCVM.WISC.EDU> Subject: Computerized vote counting To: <RISKS@csl.sri.com>

I have just completed a study of computerized vote-counting systems. The report, based on a workshop of experts in election administration and computer security, presents recommendations to improve the security and reliability of computerized vote-counting systems. The recommendations are organizational, not technical, because that is where the most important problems lie. However, five focus papers are included, including one by Willis Ware on "A Computer Technologist's View". For a free copy, please send a snail mail or email request with your complete snail mail address to

Election Computer Security Project Dept of Electrical Engineering & Computer Science The George Washington University Washington DC 20052

Lance Hoffman (LANCE@GWUVM.BITNET)

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To: risks@csl.sri.com Subject: United Airlines O'Hare Sabotage? Date: Mon, 07 Dec 87 17:36:28 EST From: Chuck Weinstock <weinstoc@SEI.CMU.EDU>

On December 3, I was traveling from California to Pittsburgh via Chicago on United. My inbound flight came in at an E gate and my outbound left from a new C gate. If an agent hadn't been there to greet the plane, I wouldn't have known it because the monitors were out. I got to the C terminal and the monitors there were on but unreadable due to jiggle (all of them.) I went to a pay phone and could not get a dial tone (on any of them.) I boarded my flight and we sat for an extra 20 minutes because "a cable had been cut" and thus they were unable to calculate the amount of fuel to load. I surmised that this was a landside cable and that all of the above events were somehow related.

I decided to call United today and learned that my surmise was true. Multiple fires in the basement of terminal 2 caused both AT&T and United wires to be severed. The former knocked out the pay phones, and the latter the airline's ability to communicate with it's computers across town.

It also seems that, at the new terminal at least, there is an automatic, underground fueling system which shut off once it detected a fire. Technicians were able to override the interlock once they determined that there was no danger due to the fire, and the pilots apparently had to do fuel calculations manually. Given that United has a new computerized baggage routing system at O'Hare, I'm really surprised that my luggage made the connection ok.

175 flights were delayed on Thursday and Friday morning. Officials suspect arson though the United spokesman I talked to could not suggest a motive. Full phone service to the terminal was not restored until Friday evening. United is awaiting licensing of a microwave system in the near future to leave themselves less vulnerable to this sort of sabotage.

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From: mogul@decwrl.dec.com (Jeffrey Mogul) Date: 7 Dec 1987 1646-PST (Monday) To: RISKS@kl.sri.com Cc: decvax!utzoo!henry@decwrl.dec.com Subject: Re: Whistle-blowers who (allegedly) aren't

Henry Spencer writes: Maybe I am just being picky about this, but it still makes me see red when I see Boisjoly described as a "whistle-blower". Boisjoly is the man who could have blown the whistle BUT DIDN'T, and seven astronauts died as a result. Boisjoly was the engineer who told MT management "don't launch", was told "put on your management hat", did so, and changed his expert professional opinion 180 degrees to match his hat color...

I recently saw a videotape of Boisjoly's appearance at MIT. I think Henry is somewhat confused; Boisjoly made it quite clear that it was another person (higher up in the management structure) who was told to "put on your management hat" and who in fact reversed his engineering opinion (and, as I recall, that was enough to overrule the other engineers). True, Boisjoly did not blow the whistle (i.e., go outside Morton Thiokol) at this point, but he says that he and other engineers were quite upset at the time, and he referred to a notebook entry he made that night expressing his fear about the next day's launch and his unease at the management actions.

What he did blow the whistle on was a coverup by Morton Thiokol of the long trail of engineering dissent over the previous year or so, due mostly to Boisjoly and several colleagues.

It is hard, even in hindsight, to say that Boisjoly himself did not do all he should have done on the eve of the launch, and is therefore criminally liable (I'll agree that his management was at fault). Who could he have gone to with just a few (nighttime) hours before the launch, with no irrefutable evidence, and no support from either his management or from NASA? (It has been suggested that NASA was under pressure from the White House to launch in time for the State of the Union speech that day; Boisjoly wouldn't have found many politicians willing to delay the launch!) In hindsight, most people would agree that he was right to object, but at the time he would have been rather isolated.

I think it is important to stress that Boisjoly (if his own account is trustworthy) was not "turning state's evidence after the fact," but rather blowing the whistle on a coverup of his internal dissent. -Jeff Mogul

P.S.: This videotape is fascinating and a lot more damning of both NASA and Morton Thiokol than my summary is. It's also quite sad; in the process of urging a room full of MIT students to be prepared to blow whistles, Boisjoly also conveys the strong personal costs of doing so. I'll try to find out how people can obtain a copy.

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Return-Path: <BNBAKER@KL.SRI.COM> Date: Mon 7 Dec 87 10:46:49-PST From: Bruce N. Baker <BNBaker@KL.SRI.COM> Subject: In "Decent Alarm"? (Re: Mariner 1 or Apollo 11? in RISKS-5.70) To: neumann@csl.sri.com

The idea of a "decent alarm" conjures up all sorts of images and fantasies for me, but perhaps Brent Chapman meant "descent alarm". Bruce [Skunked again. Thanks for descenting. PGN]

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Date: Mon, 7 Dec 87 09:16:59 PST From: Eugene Miya <eugene@ames-nas.arpa> To: risks@kl.sri.com Subject: Need for first-person anonymous reporting systems

The Mariner and F4 canopy (not computer related) stories appear to be indicative of certain types of bureaucracies. While I investigate the Mariner story (I have two leads at the moment), I think that it appears to me that normal academic reporting and publication procedures fail us in these matters. Bureaucracies don't like negative subjects to be remembered (almost, I just remembered today is Dec. 7).

If we are ever going to progress out of the software muck, we are going to have to come up with mechanisms to replace all of our ancedotal information with better information. This has to be separate from any type of watch-dog enforcement like "Golden Fleeces," ombudsmen or Inspector Generals. We have to throw out hearsay. Perhaps an anonymous Email system (lots of inherent problems) to a third party? I don't know, but it's something to think about.

--eugene miya

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Date: Mon, 7 Dec 87 12:11:57 EST From: mm@purdue.edu (Michael MacKenzie) Subject: Apollo 11 computer problems To: risks@csl.sri.com

Exerpt from Apollo, Expeditions to the Moon, Scientific and Technical Information Office, NASA, Washington D.C., 1975

During the landing of Apollo 11

Michael Collins:

At five minutes into the burn (6000 feet above the surface) ... "Program alarm", barks neil, "Its a 1202", what the hell is that? I don't have the alarm numbers memorized for my own computer, much less for the LM's I jerk out my checklist and start thumbing through it, but before I can find 1202 Houston say, "Roger, we're GO on that alarm" no problem in other words. My checklist says 1202 is an "executive overflow" meaning simply that the computer has been called upon to do too many things at once and is forced to postpone some of them. A little farther, at just 3000 feet above the surface the computer flashes 1201, another overflow condition, and again the ground is superquick to respond with assurances.

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From: treese@ATHENA.MIT.EDU Date: Sun, 6 Dec 87 22:22:52 EST To: risks@csl.sri.com Subject: Interconnected ATM networks

[Based on an article in the _Boston_Globe_, 12/5/87, p.1]

In Massachusetts now, there is a great deal of competition for ATM networks. BayBanks is by far the largest, and many other banks have joined together in a network to compete with BayBanks in sheer number of machines. BayBanks recently joined NYCE, a network of ATM's in New York. The Bank of Boston also joined, so now Bank of Boston cards work in BayBanks machines.

When the Globe contacted BayBanks, they refused to acknowledge it until told that the Globe had photographed an editor actually using a Bank of Boston card in a BayBanks machine. Pressed further, a BayBanks spokesperson admitted that it worked, and said that they didn't know NYCE was active yet.

Win Treese MIT Project Athena

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Date: Mon, 7 Dec 87 10:28:51 PST From: chapman@russell.stanford.edu (Gary Chapman) To: Risks@csl.sri.com Subject: Litigation over an expert system

I am not an attorney, but I worked as a consultant in product liability cases for eight years, and I have some comments on the question posed in RISKS about whether one can sue for damages caused by the use of an expert system.

First, who do you sue? Answer: everybody. As long as the parties mentioned in the case of a financial analyst expert system are individuals or distinct corporate entities, they can be sued and they probably will be. This is why in large product liability cases the defendants can be numerous--in cases involving DES, for example, (the drug, not the encryption system) there are literally hundreds of defendants. There does not even have to be a real legal basis for suing a defendant; it becomes incumbent on the defendant to convince the court that there is no legal basis for the lawsuit in a motion for summary judgment. There are even attorneys who specialize in finding defendants who can be sued--for example, in one case I know about, which involved a high school football player who had been paralyzed from a tackle injury during a game, a special attorney was brought in to find potential defendants, and the plaintiff wound up suing the NCAA, which had drafted the rules for playing football that were used by the plaintiff's school district.

One of the few ways in which a person or a corporation can be guaranteed protection from litigation is an indemnity agreement, or indemnity clause in a contract, which explicitly says that in the event of a lawsuit, one of the contracting parties will pick up the legal defense of the other, including all expenses and all judgments. These are pretty rare.

It is correct to assume that a disclaimer, or a warning, or a "terms of agreement" document such as is commonly found in software packages, is no protection against a lawsuit or a judgment against the developer. It is up to a judge or jury to decide whether the warning was adequate, whether it was relevant to the damages, and even whether it was presented to the user in a way that was likely to have actually "warned" the consumer about the use which produced the damages. For example, in a couple of cases I worked on, the plaintiffs brought in a psychologist who specialized in the visual impact of signs--she consulted with municipal transportation systems on how to design signs on subways that would get across essential information, for example. This psychologist would frequently testify that a warning on a product was ineffective because of the way it was packaged or designed. It is hard to estimate the effect of her testimony on a jury--sometimes the plaintiff won, sometimes the defense won. But this is an illustration of what one is likely to be up against in a case involving large damages.

In another illustration, it often comes up in product liability cases involving drugs that the warnings issued by drug companies and published in a standard reference work called the Physicians' Drug Reference, or PDR, are so dense and so full of information that they no longer convey a "warning" that is intelligible to anyone. Nevertheless, if the drug companies fail to include any particular bit of information then they may be liable for failing to provide a warning for something they knew about.

A jury may award a defendant a judgment even when there was a warning or a terms of agreement document. The defendant may then appeal the judgment based on a claim that the defendant did everything in his power to avoid the damages--for example, a lawn mower company put a big, nasty looking warning on some part of the lawn mower that said don't do such and such because you may get your hand caught in there and lose some fingers, but the plaintiff did it anyway and for some reason the jury decided he should get some money from the defendant. But appeals are expensive, and it's likely that the defendant and the plaintiff will settle the case for some dollar figure, and perhaps the money will be paid by an insurance company. There is not much one can do to predict what a jury will decide, even in the most straightforward cases. I remember asking one juror why she voted the way she did, and she said that she understood that she was supposed to give *someone* some money, and she thought the defendant could pay more than the plaintiff could. A jury may also decide that a warning could have been better, but that the plaintiff was also at least partially responsible for his injury through "contributory negligence," so the dollar amount of the judgment may be lower because of this.

In California, where I live, there is a goofy law that if one of the defendants in a multi-party suit is judged to have been responsible in any way, that defendant is liable for the percentage of responsibility, no matter how small. In other words, if the jury decides that defendant A is 99% responsible, and defendant B is only 1% responsible, and the judgment is $10 million, defendant B has to pay the plaintiff $100,000.

I don't know of any cases of product liability involving damages alleged to have occured because of the use of an expert system, but the law is likely to be the same for such cases as it is for any other product liability case.

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Date: Mon, 7 Dec 87 10:53 EST From: "Jerry Leichter (LEICHTER-JERRY@CS.YALE.EDU)" <LEICHTER@VENUS.YCC.YALE.EDU> Subject: re: Can you sue an expert system To: risks@csl.sri.com

In RISKS-5.69, Barry Stevens becomes another in a long line of people to raise the question "If an expert system gives bad advice, who can I sue?" I find it extremely disturbing that this is considered an interesting question by ANYONE, let alone by technically sophisticated people. It is a symptom of the pervasiveness of our misplaced trust in buzzwords and, more generally, in computers: If the computer said it, it MUST be right.

We have no idea how to build an expert system with anything you would want to call "understanding" or "responsibility" - or even "intelligence" - in any but the most narrow sense. There is no indication that we will be able to build such a system any time soon. An expert system is a clever way of encoding a textbook and some guidelines. If well designed, it happens to be a lot easier to use than the typical textbook - but then again there are good textbooks and poor textbooks. It should make no more sense to sue an expert system than it does to sue a textbook. It should make no more sense to sue a vendor of expert systems than it does to sue a publisher or a bookstore because of inaccurate information in one of the books they sell. It should make no more sense to sue the "knowledge engineer" who did the fairly routine work of organizing data from a group of experts into an expert system than it would to sue an editor of an encyclopedia. Finally, it should make no more sense to sue the expert who contributed to an expert system than it does to sue the author of an encyclopedia article.

As a general rule, it's almost impossible to sue someone for advice offered in a book. You need a much closer relationship with the expert - the expert has to hold himself up not just as an expert "in general", but as an expert in your particular problem. In paying for him to work on your particular prob- lem, you are creating expectations and obligations that go far beyond what you can expect from an author of a book.

In our litigious society, someone WILL sue over the advice given by an expert system. They'll sue everyone they can. They may even win, eventually. If they do it will be a sign that enough advertising, enough magazine articles, enough speeches on how "intelligent" expert systems are have been given that the courts have decided that people are legimately entitled to view this claim as more than mere "seller's talk". The first such case to be upheld is likely to see the death of the expert systems business: We do not know how to build expert systems that can come close to living up to the expectations being raised for them. No one will be able to afford the resulting liabilities. From my point of view, if it ever came to that, it would be a result richly deserved by an industry that has lived on hype. What disturbs me is that it's unlikely the legal system, should it ever start on this path, will draw quite the distinctions we in the business draw between expert systems and other kinds of applications. Would you like to be personally liable because the database program you wrote didn't deal with spelling errors and as a result someone missed an incorrectly-typed reference in an on-line catalog and was somehow injured as a result?

There is SO much hype about computers and their miraculous powers, and SO much of a willingness to believe it on the part of the public, that I think we as professionals have an obligation to tell people, at every opportunity, just how limited our real abilities are, and are likely to remain in the forseeable future. Speculations about the legal liabilities of AI's are fine as philo- sophy, but as anything more than speculation about possible futures, they are uninformed about either the technical or legal realities. If they lead people to place their trust in such systems inappropriately, then can be downright dangerous. -- Jerry

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Date: 7 Dec 87 11:49:47 PST (Monday) Subject: Re: Can you sue an expert system? From: "Bruce_Hamilton.OsbuSouth"@Xerox.COM To: portal!cup.portal!Barry_A_Stevens@Sun.COM cc: RISKS@KL.SRI.COM, "Bruce_Hamilton.OsbuSouth"@Xerox.COM

No new law needed here. I'm a layman, not a legal scholar, but it seems to me that an "expert system" is precisely analogous to a book. The only difference with a book is that you have to do all the "if-then" calculations yourself ("if your net worth according to this formula is > X, then turn to page Y..."). Bruce

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Date: Mon, 30 Nov 87 12:33:02 PST From: Bob English <lcc.bob@SEAS.UCLA.EDU> To: RISKS FORUM (Peter G. Neumann -- Coordinator) <RISKS@KL.SRI.COM> Subject: What this country needs is a good nickel chroot (Re: RISKS-5.63)

> From: "Joseph G. Keane" <jk3k+@andrew.cmu.edu> > Subject: Re: "UNIX setuid stupidity" (RISKS-5.57) > The designers of UNIX considered that a trusted program may wish to allow > operations only on a certain part of the directory tree. So they provided > the `chroot' system call, ... --Joe

Chroot doesn't work very well. Since the super-user can create device inodes, it can access or modify any disk area, regardless of the limitations enforced by the new root. 'Chroot', by itself, will not prevent a determined invader from penetrating to the rest of the system. It does, however, prevent penetrations based solely on moving through ".." --bob-- [To those of you who contributed on this topic, I STILL have a backlog of messages waiting for me to sort out the wheat from the chaff. PGN]

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