[comp.sys.mac.announce] Disinfectant 2.5

jln@casbah.acns.nwu.edu (John Norstad) (06/29/91)

Disinfectant 2.5
================

June 28, 1991

Disinfectant 2.5 is a new release of our free Macintosh anti-viral 
utility.

Version 2.5 detects the new C strain of the ZUC virus, recently discovered
in Italy. See the section on the ZUC virus in the 2.5 online manual for 
details.

Version 2.5 also recognizes the MDEF D virus. We do not believe that the D 
strain of MDEF was ever released to the public. Disinfectant recognizes it 
anyway, just in case it was inadvertently released. See the section on 
MDEF in the 2.5 online manual for details.

Neither of these two viruses is malicious, and we have no reason to believe
that either of them is widespread.

It is no longer possible to support the old 64K ROMs or operating system 
versions prior to 6.0 in Disinfectant. Beginning with version 2.5, 
Disinfectant requires a Mac 512KE or later model and system 6.0 or later. 
These restrictions are necessary because Apple's Macintosh Programmer's 
Workshop, which we use to develop Disinfectant, no longer supports the old 
ROMs or old systems.

Version 2.5 corrects an error which sometimes caused Disinfectant to crash 
after printing the online manual, especially on HP DeskWriter printers.

The online manual contains a new section titled "System 7 Notes." This 
section discusses important issues regarding viruses, Disinfectant, and 
System 7. It also describes our plans for Disinfectant 3.0. This new 
section is reproduced in full below.

Disinfectant 2.5 is available now via anonymous FTP from site 
ftp.acns.nwu.edu [129.105.113.52].  It will also be available soon on 
sumex-aim.stanford.edu, rascal.ics.utexas.edu, comp.binaries.mac, 
America Online, CompuServe, GEnie, Delphi, BIX, MacNet, Calvacom, 
AppleLink, and other popular sources of free and shareware software.

Macintosh users who do not have access to electronic sources of free and 
shareware software may obtain a copy of Disinfectant by sending a self-
addressed stamped envelope and an 800K floppy disk to the author at the 
address given below. People outside the US may send an international 
postal 
reply coupon instead of US stamps (available from any post office). Please 
use sturdy envelopes, preferably cardboard disk mailers.

People in Western Europe may obtain a copy of the latest version of 
Disinfectant by sending a self-addressed disk mailer and an 800K floppy 
disk to macclub benelux. Stamps are not required. The address is:

   macclub benelux
   Disinfectant Update
   Wirtzfeld Valley 140
   B-4761 Bullingen Belgium

System 7 Notes
==============

Disinfectant 2.5 works properly with Apple's new System 7, provided you 
remember the following three special rules:

1. Leave the Disinfectant INIT in the System Folder proper. Do not move 
the INIT to the new Extensions Folder.

2. If you try to repair an infected file, Disinfectant may tell you that 
the file is busy and recommend that you "try again without MultiFinder." 
However, you can't turn off MultiFinder in System 7. If this situation 
occurs, restart your Mac using the 800K "Disk Tools" startup floppy that 
comes with System 7 (or any other startup disk which contains an old 
System 6 startup System with MultiFinder turned off). Then run 
Disinfectant again.

3. There is one small problem with Disinfectant's custom get file dialog 
with which you can select a folder to be scanned. Don't try to select 
anything in the Desktop level in this dialog. Disinfectant may crash or 
scan the wrong object.

We are working on a new version 3.0 of Disinfectant which will fix all 
three of the problems mentioned above. Following are some other features 
planned for Disinfectant 3.0.

Version 3.0 will take full advantage of the new facilities available in 
System 7, including Balloon help, color icon families, anti-viral and 
other Apple events, icon dropping in the Finder, and proper placement of 
the Preferences file and the Disinfectant INIT file in the new Preferences 
and Extensions folders respectively.

Version 3.0 will eliminate the restriction that the INIT must load last. 
The INIT will be renamed "Disinfectant Extension."

Version 3.0 will include a new "Upgrade" command which, in the future, 
will make it possible for people to download very small upgrade files 
instead of entire new versions of the program.

The version 3.0 online manual will include a very thorough discussion of 
all the issues regarding viruses and Disinfectant as they relate to 
System 7.

We hope to release version 3.0 later this summer.

You should also be aware that System 7 is completely immune to the 
"Desktop file" viruses (WDEF and CDEF.) These viruses never activate, 
spread, or cause any damage under System 7. Both hard disks and floppy 
disks are immune to these viruses under System 7. Since the Disinfectant 
INIT detects and blocks viruses when they first try to attack your system, 
and since the Desktop file viruses never attack under System 7, the 
Disinfectant INIT will not detect them under System 7. The Disinfectant 
application, however, will still detect and remove the Desktop file 
viruses.

You should also be aware of a problem with System 7's new file sharing 
feature. If you share a folder and permit write access to it by granting 
the "make changes" privilege with the new "Sharing" command, it is 
possible 
for files in the shared folder to become infected by a virus over the 
network, even if you have the Disinfectant INIT installed on your Mac. The 
INIT will, however, prevent the virus from spreading to your non-shared 
folders. It will also completely block any attempt by the virus to execute 
it's viral code on your Mac or cause any damage to your Mac. 

We have always had the problem of viruses spreading over a network to 
files 
in writable folders on dedicated AppleShare file servers. With System 7's 
new file sharing, this has now also become a problem on personal Macs. 

Virus infection over the network is only one of many serious security 
problems with writable shared folders. Writable shared folders are 
inherently insecure, and no kind of anti-viral or other security software 
can prevent damage to their contents. To minimize these problems, we 
recommend that you limit write access to your shared folders to only 
trusted individuals. Never grant write access to guests (any user.) The 
only way to eliminate the problems completely is to never grant the "make 
changes" privilege to anyone except yourself.


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

Internet: j-norstad@nwu.edu
Bitnet: jln@nuacc
America Online: JNorstad
CompuServe: 76666,573
AppleLink: A0173