RE: Worms and CScript/WScript

[Nick FitzGerald <nick () virus-l demon co uk>]

"Richard H. Cotterell" <seec () mail retina ar> wrote:

> Ref: Nick FitzGerald <nick () virus-l demon co uk>'s
>      message dated 22 May 2002, 17:04 hours.
<<snip>>
> > ...  Thus, suggesting disabling 
> > it as a blanket recommendation may not be a wise thing...  (And, even 
> > in the corporate arena, you may better off restricting access to it 
> > rather than removing it -- if your admin group uses VB scripts for 
> > advanced system admin, certainly let them continue to run it so long 
> > as scripts can be run under a suitably privileged security context 
> > without introducing other unwanted problems but lock down your 
> > ordinary users' access to the EXEs.)
>
> An alternative approach would be to use *script defender* from AnalogX, 
> which allows a Windows user to turn on/off the whole set of scripts that 
> make for vulnerable web site visiting. :-)
>
> <http://www.analogx.com>

For SOHO users, something like that would be fine so long as they ahd
the discipline to use it.  There are several other such utilities too
and part of the discipline of using these is remembering to re-check
after installing updates and so on.  In many cases things like
ScriptDefender get turned off -- i.e. scripts get re-enabled -- for
some "good reason" and then not turned back on but the users keep
working "as normal" in the belief that the protection it was giving
them is still there.  This is not really a problem with the product 
-- more a reminder that we are talking about fixing a _process_ so a 
single point, static program is unlikely to be the be-all and end-all 
of a solution.

Further, the function of things like ScriptDefender is often 
misrepresented or misunderstood, as we see in your own description of 
what it does.  ScriptDefender provides _no_ protection against "the 
whole set of scripts that make for vulnerable web site visiting" and 
getting that wrong when offering "advice" to others is no smiling 
matter...  All ScriptDefender does is break or re-establish the file 
associations between certain _standalone_ WSH script types and the 
program(s) that normally handle them, interjecting itself into the 
command chain to allow for a presumably rational choice on the part 
of the user as to whether to let the script be passed to its usual 
handler or not.  (And let's not forget, these are the same users who, 
for the last 5 years, have largely not managed to work out you click 
the "Disable macros" button in Word and other MS Office products when 
given much the same kind of responsibility...)  It does nothing to 
disable or manage the execution of scripts embedded in web pages or 
HTML Email messages _unless_ the particular exploit of some 
vulnerability creates local "script files" of the types handled by 
ScriptDefender.


-- 
Nick FitzGerald
Computer Virus Consulting Ltd.
Ph/FAX: +64 3 3529854

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