From: rslade@cue.bc.ca (Robert Slade)
Newsgroups: comp.virus
Subject: Jerusalem virus part 2 (CVP)
Date: 23 Jul 92 23:50:00 GMT

HISVIR4.CVP   920714
 
                   The "Jerusalem" virus - part 2
 
The history of the Jerusalem virus is every bit as convoluted as its
functionality and family.  The naming alone is a fairly bizarre tale. 
As mentioned before, it was originally called the Israeli virus. 
Although considered unfair by some, it was fairly natural as the
virus had both been discovered and reported from Israel.  (Although
the virus was reported to slow down systems that were infected, it
seems to have been the "continual growth" of EXE files which led to
the detection of the virus.)  In an effort to avoid anti-semitism, it
was referred to by its "infective length" of 1813 bytes.  For COM
files.  For EXE files it was 1808 bytes.  Sometimes.  It varies
because of the requirement that the header of an EXE file is
divisible by 16.  (All quite clear?)
 
One of the early infections was found to be in an office belonging to
the Israeli Defence Forces.  This fact was reported in an Associated
Press article, and, of course, made much of.  It also gave rise to
another alias, the I.D.F. virus.
 
When the virus was first discovered, it was strongly felt that it had
been circulating prior to November of 1987.  The "payload" of file
deletion on Friday the 13th gave rise to conjecture as to why the
logic bomb had not "gone off" on Friday, November 13th, 1987. 
(Subsequent analysis has shown that the virus will activate the
payload only if the year is not 1987.)  The next following "Friday
the 13th" was May 13th, 1988.  Since the last day that Palestine
existed as a nation was May 13th, 1948 it was felt that this might
have been an act of political terrorism.  This led to another alias,
the PLO virus.  (The fact that Israel celebrates its holidays
according to the Jewish calendar, and that the independence
celebrations were slated for three weeks before May 13th in 1988 were
disregarded.  The internal structure of the virus, and the existence
of the sURIV viral programs seems to indicate that any political
correspondence is merely coincidence.)
 
Yet another alias is "sUMsDos", based upon text found in the virus
code itself.  This was, on occasion, corrupted to "sumDOS".
 
The name "Jerusalem" has gained ascendancy, possibly due to the
McAfee SCAN program identification.  (He certainly must be
responsible for the "B" designation for the "original" version.)  Of
course, the great number of variants have not helped any.  Because a
number of the variants are very closely based upon each others code,
the signatures for one variant will often match another, thus
generating even more naming confusion.  This confusion is not unique
to the Jerusalem family, of course, and is an ongoing concern in the
virus research community.
 
copyright Robert M. Slade, 1992   HISVIR4.CVP   920714
 
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