[comp.sys.mac] Disinfectant 1.4

jln@accuvax.nwu.edu (John Norstad) (12/10/89)

Disinfectant 1.4 is a new release of our free Macintosh
virus detection and repair utility.

Version 1.4 detects and repairs infections by the new
WDEF virus (see below).

In version 1.4 we no longer refer to the various clones
of the nVIR B virus by name.  We refer to them simply
as generic "clones of nVIR B."  All references to the
individual clone names have been removed from both the
document and the reports generated by the program.

We feel that the creators of these clones do not 
deserve the publicity they receive when they see the
names they have chosen in print, especially since
some of the names are offensive.

Disinfectant 1.4 is available now via anonymous FTP
from site acns.nwu.edu [129.105.49.1].  It has also
been posted to comp.binaries.mac, info-mac, and 
CompuServe, and should be available from those
sources soon.

The following text is extracted from the new section
on WDEF in Disinfectant's online document.  It 
describes what we know to date about this new virus.

The WDEF virus was first discovered in December, 1989 in 
Belgium and in one of our labs at Northwestern University. 
It has also been reported at several other major US 
universities, so we fear that it may be widespread. 
We also have reason to believe that the virus has been 
in existence since at least mid-October of 1989. 

WDEF only infects the invisible RDesktopS files used by 
the Finder. With a few exceptions, every Macintosh disk 
(hard drives and floppies) contains one of these files. 
WDEF does not infect applications, document files, or 
other system files. Unlike the other viruses, it is not 
spread through the sharing of applications, but rather 
through the sharing and distribution of disks, usually 
floppy disks.

WDEF spreads from disk to disk very rapidly. It is not 
necessary to run a program for the virus to spread.

Although the virus does not intentionally try to do any 
damage, WDEF contains bugs which can cause very serious 
problems. In particular, one bug in the virus causes the 
Mac IIci to crash. We have also noticed unusually frequent 
crashes on infected Mac IIcxs, and severe performance 
problems with infected AppleShare servers. Several people 
have also reported frequent crashes when trying to save 
files, and we have two reports that the virus can damage 
disks. 

When using Disinfectant to repair WDEF infections, you 
must use Finder instead of MultiFinder. Under MultiFinder 
the Desktop files are always Rbusy,S and Disinfectant is 
not able to repair them. If you try to repair using 
MultiFinder, you will get an error message.

Unfortunately, none of the current versions of the most 
popular virus prevention tools are effective against the 
WDEF virus. This includes Vaccine 1.0.1, GateKeeper 1.1.1, 
SymantecUs SAM Intercept 1.10, and HJCUs Virex INIT 1.12. 
However, by the time you read this, it is very likely that 
new versions of these tools will have been released. 
Symantec and HJC are preparing new releases of their products, 
and we expect that a free prevention tool or tools will also 
be available soon.

This version of Disinfectant is being released only a few 
days after the discovery of the WDEF virus. We do not yet 
understand it as thoroughly as we do the other older viruses. 
We have disassembled it completely, and we understand the basic 
replication mechanism. We know that it can cause serious 
problems, and we know why it causes some of the problems. 
Research into the behavior and adverse effects of this virus 
will continue for some time.

You should keep in touch with your local Mac user group or 
bulletin board for more information about this new virus as 
it becomes available. Commercial online services like 
CompuServe and Genie and the Macintosh trade press publications 
like MacWeek are also good sources of information. 

John Norstad
Academic Computing and Network Services
Northwestern University
2129 Sheridan Road
Evanston, IL 60208

Bitnet: jln@nuacc
Internet: jln@acns.nwu.edu
CompuServe: 76666,573
AppleLink: A0173