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- RUMORS OF WORMS AND TROJAN HORSES
- Danger Lurking in the Public Domain
-
- introduced and edited by Mike Guffey
-
- -INTRODUCTION
-
- There are literally thousands of free (or nearly free) programs
- available in computerdom's Public Domain. Those who use them save
- hundreds of dollars and thousands of hours. But many sneer at
- the idea of anything worthwhile being "free". Thus personal
- computing becomes divided into two camps: those who believe there
- are two camps and the rest who use Public Domain software (but
- sport no sense of moral superiority).
-
- For several years now rumors have circulated about dangerous
- programs which, when run, infest the innards of personal
- computers like parasites. And unlike most software, these
- insideous programs don't go away when the power is shut off. The
- story is they invade ROMs and "eat" memory away each time
- hardware is powered up.
-
- The legends have a basis in fact. For such horrors =do= exist in
- the world of mainframes. Probably first created by a bored or
- disgruntled programmer, such programs have been unleashed inside
- some of this country's largest computers. Generally, they are
- not outwardly visible, but begin the attack like a low grade
- fever. And these horrible little strings of code do damage a
- little at a time, slowly building in intensity. At first, things
- start going slightly awry. Ultimately, the system crashes or
- must be shut down. One recent magazine article called these
- creations "computer viruses". Just =how= damaging such programs
- can be (or have been) has not been fully publicized. But the
- facts lie on a razor's edge between science fiction and
- tomorrow's headlines. They are believed to pose a serious
- potential threat to national security.
-
- Some say the first of such monsters appeared on computer bulletin
- boards (BBS's) named "WORM.COM". [Remember that it is only
- recently that any online descriptions began to be posted next to
- program names. Some BBS's, notably CP/M based systems, still do
- not offer any explanation beyond the program name or notes in the
- associated message base part of the system.] And almost every
- computer user group has at least one experienced member who can
- tell the horrible tales of what these programs do. Actual
- witnesses to the destruction or victims of the atrocities seem to
- be =very= rare.
-
- Related to the twisted thinking behind such criminal mischief is
- the so-called "TWIT" phenomenon. Twits are computer vandals who
- glory in breaking into and "crashing" or seriously damaging
- remote computer systems. The targets range from neighborhood
- BBS's to any large computers which can be accessed via phone
- lines. And while such mental midgets have beeâ•–hglorified in the
- media and mis-labeled as "hackers", their very existence causes
- hysteria in and amongst the non-computing public at large.
-
- Computer security for large and small remote computer systems is
- getting better at screening out or scaring off "twits". But they
- still exist. There are indications that some have graduated from
- incessant attempts to break into BBS's. Instead they bring forth
- Trojan horses: damaging programs disguised as utilities and
- mis-labled or misdocumented as new treasures of the Public
- Domain.
- ===]#[===
-
- The following data was recently retreived from a California BBS:
-
- WARNING! DANGEROUS PROGRAMS
-
- 1) Warning: Someone is [or may be] trying to destroy your data.
- Beware of a SUDDEN upsurge of [spurious] programs on Bulletin
- Boards and in the Public Domain. These programs purport to be
- useful utilities, but, in reality, are designed to sack your
- system.
-
- One has shown up as EGABTR, a program that claims to show you how
- to maximize the features of IBM'S Enhanced Graphics Adapter. It
- has also been spotted renamed as a new super-directory program.
- It actually erases the (F)ile (A)llocation (T)ables on your hard
- disk, [thereby rendering all data useless and inaccessible]. For
- good measure, it asks you to put a disk in Drive A:, then another
- in Drive B:. After it has erased those FATs too, it displays,
-
- " Got You! Arf! Arf! "
-
- Don't [casually] run any public-domain program that is not a
- known quantity. Have someone you know and trust vouch for it.
- ALWAYS examine it FIRST with DEBUG [or DDT or a similar
- utility]. Look at all the ASCII strings and data. If there is
- anything even slightly suspicious about it, [either] do a cursory
- disassembly [or discard it]. [For MSDOS programs] be wary of
- disk calls (INTERRUPT 13H), especially if the program has no
- business writing to the disk. Run your system in Floppy only
- mode with write protect tabs on the disk or junk disks in the
- drives.
-
- Speaking of Greeks bearing gifts, Aristotle said that the
- unexamined life is not worth living. The unexamined program [may
- not be] worth running.
-
- - from The Editors of PC
- July 23, 1985
- Volume 4, Number 15
-
-
- 2) Making the rounds of the REMOTE BULLETIN BOARDS [is] a program
- called VDIR.COM. It is a little hard to tell what the program is
- suppose to do.
-
- What it actually does is TRASH your system. It writes garbage
- onto ANY disk it can find, including hard disks, and flashes up
- various messages telling you what it is doing. It's a TIME BOMB:
- once run, you can't be sure what will happen next because it
- doesn't always do anything immediately. At a later time, though,
- it can CRASH your system. Anyway, you'd do well to avoid
- VDIR.COM. I expect there are a couple of harmless, perhaps even
- useful, Public Domain programs floating about with the name VDIR;
- and, of course, anyone warped enough to launch this kind of trap
- once, can do it again. Be careful about untested "free"
- software.
-
- [paraphrased from
- Computing at Chaos Manor
- From the living Room
- By Jerry Pournelle
- BYTE Magazine, The small systems Journal]
-
-
- Two other examples of this type of program:
-
- 1. STAR.EXE presents a screen of stars then copies RBBS-PC.DEF
- and renames it. The caller then calls back later and d/l the
- innocently named file, and he then has the SYSOP'S and all the
- Users passwords.
-
- 2. SECRET.BAS This file was left on an RBBS with a message saying
- that the caller got the file from a mainframe, and could not get
- the file to run on his PC, and asked someone to try it out. When
- it was executed, it formatted all disks on the system.
-
- We must remember, that there are a few idiots out there who get
- great pleasure from destroying other peoples' equipment.
- Perverted I know, but we, the serious computer users, must take
- an active part in fighting against this type of stuff, to protect
- what we have. Be sure to spread this [message] to other BBS's
- across the country so that as many people as possible will be
- aware of what is going on.
-
- [from
- The Flint Board
- Flint, Mich
- (313) 736-8031]
- ===]#[===
-
- -EPILOGUE
-
- Got your attention? There is no need to hatchet your modem and
- erase your communications software. While such programs can do
- tremendous damage, they are, fortunately, very rare. The
- following is an expansion of the countermeasures suggested
- above.
-
- A) Never, NEVER, N>E>V>E>R>! download and run Public Domain
- software (the first time) on a hard disk. While many programs
- are well known, it is a logical presumption that Trojan
- horse-type programs may have been uploaded with the name of a
- well-known utility. Or as a new version of one of your old
- favorites. Download them to a blank floppy or to a disk you have
- a current backup copy of.
-
- B) Get in the habit of examining unknown software with HEX/ASCII
- utilities that will reveal copyright data, documentation, program
- error and prompt messages. A good choice in MSDOS is called
- PATCH.COM and in CP/M there is DUMPX.COM. Even if a program is
- written in protected BASIC, you may still be able to find some
- useful data this way. [This is also a way to find documentation
- within programs without .DOC files or descriptions.]
-
- C) Be wary of text files suggesting patches with DEBUG or DDT
- that you do not understand. ALWAYS make such modifications to a
- backup copy of your .COM, .EXE, .OVR files. There are no known
- examples of Trojan horses appearing this way, but...
-
- D) Make those BBS's which screen programs before making them
- available your first (but not your only) choice for acquiring new
- PD software. If you cannot figure out what a program does,
- =don't= upload it to some other BBS.
-
- E) Be wary but not paranoid. Be careful but not overcautious.
- Do not fan the fires of hysteria by passing along rumors of worms
- and Trojan horses. Speak of what you =know=. There are alot of
- good public domain programs that will do what you need. And when
- you find it, pass it along.
-
- -end-