[comp.virus] Is virus infection by inserting floppy disk possible?

diblasi@mail-gw.ncsl.nist.gov (Thomas DiBlasi) (04/09/91)

Hi,

I've been monitoring Virus-l digest since December and now for the
first time have a question.

Is it possible for a virus, trojan, worm, etc. to infect a hard disk
or RAM simply by inserting an infected floppy into a drive without
execution??

I thought I saw something on how some PC's /MAC's can recognize the
presence of a floppy after insertion without the benefit of an access
command being entered.

p1@arkham.wimsey.bc.ca (Rob Slade) (04/12/91)

diblasi@mail-gw.ncsl.nist.gov (Thomas DiBlasi) writes:

> Is it possible for a virus, trojan, worm, etc. to infect a hard disk
> or RAM simply by inserting an infected floppy into a drive without
> execution??

A short answer: on a Mac, yes.  However, most of the Mac virus protection
programs do automatic detection on disk insertion.

On a PC: no.  Or at least, not with standard machines.  (I use an old NEC
laptop for my comm sessions, and it growls at every disk insertion so it
must be doing *something*.  But most PC's don't.)

=============
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mike@pyrite.SOM.CWRU.Edu (Michael Kerner) (04/12/91)

That's what WDEF viruses do on the Macintosh - they transfer from the
"desktop" file of the infected floppy to the host.  However, they are
also extremely easy to kill, and don't do any real damage, so they are
not (yet) seen as a big threat.

Mikey.
Mac Admin
WSOM CSG
CWRU
mike@pyrite.som.cwru.edu

CAH0@gte.com (Chuck Hoffman) (04/15/91)

diblasi@mail-gw.ncsl.nist.gov (Thomas DiBlasi) writes:
>
> Is it possible for a virus, trojan, worm, etc. to infect a hard disk
> or RAM simply by inserting an infected floppy into a drive without
> execution??

Yes, the WDEF virus on the Macintosh can do this.  By the time the
icon for the floppy appears on the screen, ALL the disks shown on the
screen will have been infected, both hard disks and floppies.  WDEF is
benign, and is easily deleted, and is detected by Virex before the
icon appears on the screen, but the answer to your question is yes.

WDEF is the only virus I have been hit with.  A friend sent me a text
file with a description of (you guessed it) WDEF infections!  I also
got a shrinkwrapped diskette from a software subscription service
which had WDEF on it, but by then I had Virex on the system so the
system did not pick up the WDEF.

- - Chuck Hoffman, GTE Laboratories, Inc.  |  I'm not sure why we're here,
cah0@bunny.gte.com                       |  but I am sure that while we're
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F8DY@VAX5.CIT.CORNELL.EDU (04/17/91)

mike@pyrite.SOM.CWRU.Edu (Michael Kerner) writes:
> That's what WDEF viruses do on the Macintosh - they transfer from the
> "desktop" file of the infected floppy to the host.  However, they are
> also extremely easy to kill, and don't do any real damage, so they are
> not (yet) seen as a big threat.

It may be easy to kill (rebuild your desktop!) but it also spreads
like wildfire.  And it certainly does do "real damage" -- where I
work, people have lost papers because WDEF crashed their system and
corrupted their files.  It causes printing problems, it crashes a Mac
II almost immediately, and God help you if you get it on a server!

In reply to the original question, CDEF (Mac) also works like this:
infecting the desktop file, usually on disk insertion.  And since it
was written at Ithaca High School, it is _all_over_ Cornell.  (Lucky
us.)


              _____________________________________________
    |        /                \           /                \        |
    |       / You can't fight  |         |   Mark Pilgrim   \       |
    |      |  in here -- this  |\_______/|                   |      |
     \_____|  is the WAR ROOM! |//     \\|   f8dy@cornella.  |_____/
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 My thoughts may not be my own, but they're certainly not my employer's.

ingoldsb%ctycal@fsa.cpsc.ucalgary.ca (Terry Ingoldsby) (04/18/91)

p1@arkham.wimsey.bc.ca (Rob Slade) writes:
...
> On a PC: no.  Or at least, not with standard machines.  (I use an old NEC
> laptop for my comm sessions, and it growls at every disk insertion so it
> must be doing *something*.  But most PC's don't.)

I recently installed a floppy disk drive on a non-PC computer
(actually a Radio Shack Color Computer).  I bought the drive without
power supply or cabinet and assembled the unit myself.  I discovered
that the drive would cycle the power on for about 5 seconds every time
a disk was inserted, even when the drive was not connected to a
computer.  It appears to be a feature that makes certain the disk has
seated itself properly before any data operations take place.  As far
as I could tell the computer is not advised of the insertion.  Perhaps
this is what you are experiencing?

- --
  Terry Ingoldsby                ingoldsb%ctycal@cpsc.ucalgary.ca
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slandrum@apple.com (Stephen Landrum) (04/19/91)

CAH0@gte.com (Chuck Hoffman) writes:
> [ ... ]  WDEF is
>benign, and is easily deleted, [ ... ]

The Hitchiker's Guide to Computer Virii entry for the WDEF virus is
"Benign".  Ford Prefect and I would like to change the entry to
"Mostly Benign".  :-)

We have a lot of Mac IIci's at work, and there is a bug in WDEF (yea,
a bug in a virus :-) ) that causes it to crash the IIci when a disk
with WDEF on it is inserted in the floppy drive.  Fortunately, this
flaw means it never gets installed on the IIci, but it can be
frustrating if you don't have some INIT installed that catches WDEF
and removes it before it crashes the machine.

- --
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