Text File

RISKS-LIST: RISKS-FORUM Digest Wednesday 4 January 1989 Volume 8 : Issue 2

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

Contents: Christmas 1988 Decnet Worm -- Counteracted (Cliff Stoll) Vincennes and the computer (Steve Philipson, Clifford Johnson) Viruses and System Security (a story) (by Dave Platt, submitted to RISKS from rec.humor.funny by Jim Horning and Mark Brader) Stallman, Minsky and Drescher on the Internet Worm (via Martin Minow) FAA Orders Computer Card Security Systems at 270 Airports (Henry Mensch)

The RISKS Forum is moderated. Contributions should be relevant, sound, in good taste, objective, coherent, concise, and nonrepetitious. Diversity is welcome.

* RISKS MOVES SOON TO csl.sri.com. FTPable ARCHIVES WILL REMAIN ON KL.sri.com. CONTRIBUTIONS to RISKS@CSL.SRI.COM, with relevant, substantive "Subject:" line (otherwise they may be ignored). REQUESTS to RISKS-Request@CSL.SRI.COM. FOR VOL i ISSUE j / ftp KL.sri.com / login anonymous (ANY NONNULL PASSWORD) / get stripe:<risks>risks-i.j ... (OR TRY cd stripe:<risks> / get risks-i.j ... Volume summaries in (i.j)=(1.46),(2.57),(3.92),(4.97),(5.85),(6.95),(7.99).

----------------------------------------------------------------------

Date: Tue, 27 Dec 88 13:44:27 EST From: cliff%cfa204@harvard.harvard.edu (Cliff Stoll) Subject: Christmas 1988 Decnet Worm -- Counteracted

On December 22nd, someone started a virus/worm on the SPAN/Decnet network. It attacks only Vax/VMS computers, and only those which are connected to the SPAN/HEPNET/Decnet network. It cannot enter Unix systems or PC's.

This virus/worm is benign in that it does not erase information. The writer apparently wishes to embarrass system managers and network administrators.

Language purists will call it a worm: it does not modify any files, and copies itself from node to node.

Indications point to an origin in Germany.

I spent several hours creating bogus announcements to confuse and counteract the virus writer. I've mailed these to the PHSOLIDE collection point.

The virus writer has collected these announcements, and has no way to tell which announcements are valid, and which are phoney.

Technical details for Decnet/VMS people:

The worm enters through the Decnet Task object, and mails your system's announcement banner (sys) to Decnet node 20597::PHSOLIDE. (This node apparently is in France)

The worm generates a random node address and tries to copy itself onto that node. If this fails, it tries different random nodes until it finds one. Once it finds a valid node, it tries to copy itself using the NETFAL account (through the Task object). If you don't have a valid Task object, it tries to log into account DECNET, with password DECNET.

Once it's in your system, it creates a list of all users on your node, and mails a message to each of them. This message is some blather about how Father Christmas has had a hard time getting "the terrible Rambo-Guns, Tanks and Space Ships up here at the Northpole." The message itself is written in a stilted, almost Germanic, style.

You can immunize your system by deleting the TASK 0 Decnet object, and by making certain that you've changed the Decnet password. In any case, the worm is timed to stop after December 24th. By the time you receive this message, the worm will have died.

Cliff Stoll, Harvard - Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 Cliff@cfa200.harvard.edu

------------------------------

Date: Fri, 23 Dec 88 15:03:50 PST From: Steve Philipson <steve@aurora.arc.nasa.gov> Subject: Vincennes and the computer

In RISKS-FORUM Digest 7.94 "Clifford Johnson" <GA.CJJ@Forsythe.Stanford.EDU> [Vincennes: conclusively, a computer-related error] writes:

>I reflect that *all* the information that panicked the Vincennes crew and >captain came from the computers. The captain was not faulted [...] > The fault was found to lie largely with the computer's initial >classification of the flight as hostile, and the computers' subsequent unclear >albeit correct presentation of the ascent data. The actions taken to remedy >the deficiencies are improvements in the computer display/ human interface. >This is a a classic case of computer *related* error: unobvious and secondary >display of criticial data.

>What the Pentagon has has more or less overtly ruled is that its >most competent, trained, and alert officers cannot be blamed for >mistakenly reading and acting on deadly computer displays, >especially not in combat, i.e. when they're actually used.

In the case of Vincennes, the computer was definitely NOT the only nor the most significant source of information. The ship had been primed with intelligence reports of hostile intent, was engaged in battle, maneuvering radically, and taking fire. The crew could hear bullets and shrapnel hitting the ship. They had been briefed to expect attack including aerial attack, and had the memory of the Stark to remind them of the dangers inherent in their situation. They knew they were under surface attack. They were ready to believe that they were about to come under aerial attack as well.

A major conclusion of the report was that people under great stress do not function in the same manner as they do in lab conditions. It's easy for us to scour through the records in the comfort of our homes and offices and make judgements, but far more difficult to make them under severe time pressure, in physically disturbing conditions, under the threat of death.

This case illustrated that a correct presentation of data is not always sufficient to prevent error; it may be necessary to present the data correctly and in a form that is highly unlikely to be misinterpreted. It is not clear that we will ever be able to make systems that are immune from misinterpretation under such severe conditions.

There is always confusion in battle, and there always will be, no matter what we do with computer systems. The commander's first duty was to protect his ship. That is what he did, albeit from what turned out to be a non-combatant that could not have hurt him. To censure the crew of the Vincennes would undermine the ability of every man in uniform to take the necessary actions to protect himself and his country. The Pentagon brass affirmed with their decision that battle zones are places rife with confusion and danger, and that errors under those conditions are a fact of life.

We learn from this incident that battle zones are no place for innocents (a lesson that is intuitively obvious), and that we have much to learn about how to fight with systems based on men and machines.

[...]

------------------------------

Date: Tue, 27 Dec 88 16:19:08 PST From: "Clifford Johnson" <GA.CJJ@Forsythe.Stanford.EDU> Subject: Vincennes and the computer

> In the case of Vincennes, the computer was definitely NOT the only > nor the most significant source of information.

What I meant was that without the computer, there wouldn't have even been a decision to shoot. The computer-sensor's recognition of military signals from the take-off airfield triggered, according to rule, an initial misclassification as hostile until proven otherwise, and without the computers' tracking of the flight nobody could have believed that the flight was diving towards the ship. That the error was due to bad presentation of data was the Pentagon's conclusion, and why the incident is conclusively computer-related error.

> To censure the crew of the Vincennes would undermine the > ability of every man in uniform to take the necessary actions > to protect himself and his country.

We agree that the conduct of men in such circumstances is inherently an input-governed impulse. But your sentiment overlooks that military mission takes precedence over personal survival, and that protection of innocent life in the Gulf was the Vincennes' mission. Viewed in this light, the reliance placed on the computer-governed drills is unconvincingly justified.

[...]

------------------------------

Date: 21 Dec 1988 1349-PST (Wednesday) From: horning@src.dec.com (Jim Horning) Newsgroups: rec.humor.funny Subject: Viruses and System Security (a story) [by Dave Platt] Date: 20 Dec 88 00:30:03 GMT Sender: funny@looking.UUCP Reply-Path: watmath!uunet!arthur.cs.purdue.edu!bee Also-Submitted-To-RISKS-by: From: Mark Brader <msb@sq.sq.com>

The following story was posted in news.sysadmin recently.

The more things change, the more they stay the same...

Back in the mid-1970s, several of the system support staff at Motorola (I believe it was) discovered a relatively simple way to crack system security on the Xerox CP-V timesharing system (or it may have been CP-V's predecessor UTS). Through a simple programming strategy, it was possible for a user program to trick the system into running a portion of the program in "master mode" (supervisor state), in which memory protection does not apply. The program could then poke a large value into its "privilege level" byte (normally write-protected) and could then proceed to bypass all levels of security within the file-management system, patch the system monitor, and do numerous other interesting things. In short, the barn door was wide open.

Motorola quite properly reported this problem to XEROX via an official "level 1 SIDR" (a bug report with a perceived urgency of "needs to be fixed yesterday"). Because the text of each SIDR was entered into a database that could be viewed by quite a number of people, Motorola followed the approved procedure: they simply reported the problem as "Security SIDR", and attached all of the necessary documentation, ways-to-reproduce, etc. separately.

Xerox apparently sat on the problem... they either didn't acknowledge the severity of the problem, or didn't assign the necessary operating-system-staff resources to develop and distribute an official patch.

Time passed (months, as I recall). The Motorola guys pestered their Xerox field-support rep, to no avail. Finally they decided to take Direct Action, to demonstrate to Xerox management just how easily the system could be cracked, and just how thoroughly the system security systems could be subverted.

They dug around through the operating-system listings, and devised a thoroughly devilish set of patches. These patches were then incorporated into a pair of programs called Robin Hood and Friar Tuck. Robin Hood and Friar Tuck were designed to run as "ghost jobs" (daemons, in Unix terminology); they would use the existing loophole to subvert system security, install the necessary patches, and then keep an eye on one another's statuses in order to keep the system operator (in effect, the superuser) from aborting them.

So... one day, the system operator on the main CP-V software-development system in El Segundo was surprised by a number of unusual phenomena. These included the following (as I recall... it's been a while since I heard the story):

- Tape drives would rewind and dismount their tapes in the middle of a job.

- Disk drives would seek back&forth so rapidly that they'd attempt to walk across the floor.

- The card-punch output device would occasionally start up of itself and punch a "lace card" (every hole punched). These would usually jam in the punch.

- The console would print snide and insulting messages from Robin Hood to Friar Tuck, or vice versa.

- The Xerox card reader had two output stackers; it could be instructed to stack into A, stack into B, or stack into A unless a card was unreadable, in which case the bad card was placed into stacker B. One of the patches installed by the ghosts added some code to the card-reader driver... after reading a card, it would flip over to the opposite stacker. As a result, card decks would divide themselves in half when they were read, leaving the operator to recollate them manually.

I believe that there were some other effects produced, as well.

Naturally, the operator called in the operating-system developers. They found the bandit ghost jobs running, and X'ed them... and were once again surprised. When Robin Hood was X'ed, the following sequence of events took place:

!X id1

id1: Friar Tuck... I am under attack! Pray save me! (Robin Hood) id1: Off (aborted)

id2: Fear not, friend Robin! I shall rout the Sheriff of Nottingham's men!

id3: Thank you, my good fellow! (Robin)

Each ghost-job would detect the fact that the other had been killed, and would start a new copy of the recently-slain program within a few milliseconds. The only way to kill both ghosts was to kill them simultaneously (very difficult) or to deliberately crash the system.

Finally, the system programmers did the latter... only to find that the bandits appeared once again when the system rebooted! It turned out that these two programs had patched the boot-time image (the /vmunix file, in Unix terms) and had added themselves to the list of programs that were to be started at boot time...

The Robin Hood and Friar Tuck ghosts were finally eradicated when the system staff rebooted the system from a clean boot-tape and reinstalled the monitor. Not long thereafter, Xerox released a patch for this problem.

I believe that Xerox filed a complaint with Motorola's management about the merry-prankster actions of the two employees in question. To the best of my knowledge, no serious disciplinary action was taken against either of these guys.

Several years later, both of the perpetrators were hired by Honeywell, which had purchased the rights to CP-V after Xerox pulled out of the mainframe business. Both of them made serious and substantial contributions to the Honeywell CP-6 operating system development effort. Robin Hood (Dan Holle) did much of the development of the PL-6 system-programming language compiler; Friar Tuck (John Gabler) was one of the chief communications-software gurus for several years. They're both alive and well, and living in LA (Dan) and Orange County (John). Both are among the more brilliant people I've had the pleasure of working with.

Disclaimers: it has been quite a while since I heard the details of how this all went down, so some of the details above are almost certainly wrong. I shared an apartment with John Gabler for several years, and he was my Best Man when I married back in '86... so I'm somewhat predisposed to believe his version of the events that occurred.

Dave Platt Coherent Thought Inc. 3350 West Bayshore #205 Palo Alto CA 94303

-- Edited by Brad Templeton. MAIL, yes MAIL your jokes to funny@looking.UUCP Attribute the joke's source if at all possible. I will reply, mailers willing. Remember: If you POST your joke instead of mailing it, I will not reply.

------------------------------

Date: 20 Dec 88 14:53 From: minow%thundr.DEC@decwrl.dec.com Subject: Stallman, Minsky and Drescher on the Internet Worm

The following letter appeared in the Business section of the Boston Globe, 20 Dec 1988. [It does not represent the position of Digital Equipment Corporation (or my position, either). Martin Minow]

Recent computer virus threatens American justice system, too

The recent computer network virus was a prank designed to be harmless. A minor programming error made it replicate so much that it clogged Internet, a research network, with messages. Now some people want to punish this accident as deliberate sabotage.

Yes, people should not clog networks. But the "worm" had parts designed to avoid clogging; one had an error. Research is error prone: punishing errors is futile if limited to errors in pranks. More rational is to keep critical computers off research networks, as the military does.

Yes, another worm might be designed to destroy files. Some people are angry at these potential future crimes; so angry that they clamor to punish someone as an example, whether his own deeds deserve it or not.

This clamor threatens the American tradition of justice for each individual -- something even more valuable than a working Internet.

Richard Stallman Free Software Foundation, Cambridge.

Henry Minsky and Gary Drescher MIT Artificial Intelligence Laboratory, Cambridge.

------------------------------

Date: Wed, 4 Jan 89 23:05:01 EST From: henry@GARP.MIT.EDU (Henry Mensch) Subject: FAA Orders Computer Card Security Systems at 270 Airports

(NY Times, 4 Jan 89) NEW YORK -- In a sweeping new move to tighten security at United States airports, the government Wednesday ordered that computer card systems be installed at the busiest terminals by early 1991 to keep people who might threaten airline safety from reaching restricted areas. Ultimately, a total of 270 airports would have to install either computer card systems, resembling those used for automatic banking, or alternative methods providing equal security. The Federal Aviation Administration rule, estimated to cost $170 million over the next 10 years, was proposed in March.

The move was made as a result of the crash of a Pacific Southwest Airlines commuter jet in December 1987 that occurred after a passenger, believed to have been an employee dismissed by an that had bought PSA, fired several gunshots during the flight. All 43 people aboard were killed.

The decree Wednesday had additional significance in the aftermath of the bombing of a Pan Am jumbo jet over Scotland last month in which a total of 270 people were killed.

In a section of the rule justifying its action, the FAA said currently used identification badges "provide a means of control once an individual has gained access to a restricted area." "The FAA is concerned," it said, "that these procedures could allow an individual using forged, stolen or noncurrent identification to compromise the secured areas." It added that former employees could use their familiarity with procedures to enter a "secured area and possibly commit a criminal act on board an aircraft." [...] Burnley noted in Wednesday's announcement that computer-controlled card systems could be programmed to "keep a record of employees who try to enter areas for which they are not authorized." "They can also reject cards that have been reported lost or stolen, or which have not been surrendered by former employees," he said.

T. Allan McArtor, administrtator of the FAA, said such systems already were in use at some airports and "have proved to be highly effective and workable."

Airline officials and airport operators had advanced many objections to the new rule, including the high cost of installing and operating the computer-card or other systems. But in dealing with the cost issue, the FAA said the total investment "can be recovered fully if one incident, involving the loss of 170 lives and a wide-bodied jet," were prevented in the next 10 years. [...]

------------------------------

End of RISKS-FORUM Digest 8.2 ************************