full-disclosure - BZIP2 bomb question

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From: chows at ozemail.com.au (Gregh)
Subject: BZIP2 bomb question

Please note I am not a good programmer here but here goes:

I am wondering why, for those who HAVE to auto unpack, a script cannot be
written which, upon receipt of an archive of any sort, inspects it for, as
an example, 100K of the same character repeated (keeping in mind that the
NULL character, chr$(7) etc have all been used for compressed bombs) and if
there *IS* such a file, move the file to some safe location for later manual
inspection and if not, allow automatic unpacking etc.

Surely this would be a 5 minute script for SOMEONE who knows how to do it
well? Even if it wont work on receipt of compressed archives, it could be a
timed even to happen, say 10 minutes before the actual auto unpacking is to
occur if that is done at a particular time.

I used to be a "dabbler" programmer on a machine back in the 80s where we
used to have this same sort of problem and because the services provided
could not be interrupted, the above was how I got around it.

Greg.