Vuln Dev
creating a "cc" opcode from ASCII shell code Jun 22 2007 09:58AM
Aaron Adams (aadams securityfocus com) (3 replies)
Re: creating a "cc" opcode from ASCII shell code Jun 23 2007 12:09AM
Dude VanWinkle (dudevanwinkle gmail com)
Re: creating a "cc" opcode from ASCII shell code Jun 22 2007 10:02PM
H D Moore (sflist digitaloffense net)
Re: creating a "cc" opcode from ASCII shell code Jun 22 2007 06:20PM
Valdis Kletnieks vt edu
On Fri, 22 Jun 2007 03:58:24 MDT, Aaron Adams said:

> Maybe I am just tired.... My guess is that I must
> seed a register with an ASCII value and then
> and/xor/not it with approriate value. I have tried
> using add/sub with no luck.

Yes, that's your best option at that point - you can't get a 0xcc
in there because of the 0z10-0z79, but you *can* start with a 0x40,
shift that left 1 to get a 0x80, and then OR that into a 0x4c.

(Getting a shift-left may be a problem - if so, try "multiply by 2"
or "add to itself" or similar alternatives. Maybe loading a 16-bit
0x4020 and shifting it *right* 7 bits will work. Play around. ;)
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