[Esa-l]Adobe PDF files can be used as virus carriers (fwd)
klaus at compt.com
Tue Aug 7 21:16:04 PDT 2001
> > Will it allow programs to be EXECUTED, though? On many OSes,
> > one can execute anything one can read; that is, the permissions
> > are not separate. And if the program is a script, read permission
> > may be all that's necessary, because the script is really just
> > "data" for the interpreter.
> The point is that it's a known issue, which has had solutions out there
> for many years. For Unix, any client invoking gs on possibly bad data
> (eg, most viewers) should be passing -dSAFER by default.
The same option applies to the GNU [tn]roff formatters, [tn]roff has
similar(ly obscure) file manipulation capabilities, like PostScript; there
was a fair bit of talk about that subject on the BUGTRAQ list about a year
or so ago; does the procmail security kit scan for those macros as well?
The only drawback to mangling something like nroff or postscript is that
the language syntax is not a commonly known one, so fixing up defanged files
can be onerous. ... unless you use sed or something, and strip out a
predictable 'DEFANGED' string.
Does TeX have similar file capabilities? (slightly off-topic, but just for
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