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Re: BZIP2 bomb question
From: "Alex Shipp" <ashipp () messagelabs com>
Date: Mon, 12 Jan 2004 21:36:54 -0000
----- Original Message ----- From: "Gregh" <chows () ozemail com au>
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.
Ignoring lots of technical details (!) this can indeed be done, and can be used along with lots of other heuristics to defend against compressed bombs. There are implementaions that already do this. Regards, Alex ________________________________________________________________________ This email has been scanned for all viruses by the MessageLabs Email Security System. For more information on a proactive email security service working around the clock, around the globe, visit http://www.messagelabs.com ________________________________________________________________________ _______________________________________________ Full-Disclosure - We believe in it. Charter: http://lists.netsys.com/full-disclosure-charter.html
Current thread:
- BZIP2 bomb question Gregh (Jan 12)
- RE: BZIP2 bomb question Alexander Veit (Jan 12)
- Re: BZIP2 bomb question Alex Shipp (Jan 12)
- Re: BZIP2 bomb question Gregh (Jan 13)
- RE: BZIP2 bomb question Steve Wray (Jan 12)
- Re: BZIP2 bomb question Dr. Peter Bieringer (Jan 13)