Re: [Full-Disclosure] Re: New whitepaper: Writing IA32 Restricted Instruction Set Shellcode Decoder Loops

["Berend-Jan Wever" <skylined () edup tudelft nl>]

Code examples ?
Check out the "Shellcode encoders" source codes on my webpage.

Cheers,
SkyLined

PS. please send any discussions on the paper in pm to skylined () edup tudelft nl or #SkyLined on EFNet

----- Original Message ----- 
From: "Michael Vergoz" <descript () secureyourapache com>
To: "Peter Willis" <psyphreak () phreaker net>
Cc: <full-disclosure () lists netsys com>; <vuln-dev () securityfocus com>; "Berend-Jan Wever" <skylined () edup 
tudelft nl>
Sent: Thursday, November 18, 2004 09:04
Subject: [Full-Disclosure] Re: New whitepaper: Writing IA32 Restricted Instruction Set Shellcode Decoder Loops


> Hi,
>
> Nice paper.
> Some code examples should be great (i think).
> A question : what about false-disassembly into shellcode ?
>
> like :
> mov eax, eax
> [...]
> jmp false
> db 0xAA
> [...]
> false:
> mov eax, 1
> int 0x80
> [...]
>
> mv
>
> On 17 nov. 04, at 23:00, Peter Willis wrote:
>
> > Hey, cool paper. Speaking of phrack, if in the future you have an 
> > article you think is print-worthy but is rejected by most zines, try 
> > sending it to Binary Revolution <articles () binrev com>. Although 
> > they're newer and have had some delays in getting new issues out, 
> > they're starting to re-focus on the magazine and the number of their 
> > supporters is growing. Sorry if this comes off a little advertisey, 
> > but hopefully if more people write in then BinRev can publish more 
> > original articles about vulnerabilities which can then make it back 
> > onto the web as sample articles.
> >
> > Berend-Jan Wever wrote:
> >
> > > Hi all,
> > >
> > > This one got rejected by phrack and I couldn't be arsed to rewrite it 
> > > so it would make the next edition:
> > > "Writing IA32 Restricted Instruction Set Shellcode Decoder Loops" by 
> > > SkyLined
> > > ( http://www.edup.tudelft.nl/~bjwever/whitepaper_shellcode.html )
> > >
> > > The article addresses the requirements for writing a shellcode 
> > > decoder loop using a limited number of characters that limits our 
> > > instruction set. Most of it is based on my experience with 
> > > alphanumeric decoders but the principles apply to any piece of code 
> > > that is written to work with a limited instruction set. (It's a 
> > > continuation on rix's and obscou's work for phrack).
> > >
> > > Comments and questions welcome, but I can not guarantee an answer to 
> > > n00b questions.
> > >
> > > Cheers,
> > > SkyLined
> > >
> > > http://www.edup.tudelft.nl/~bjwever
> > > <skylined () edup tudelft nl>
>
> _______________________________________________
> Full-Disclosure - We believe in it.
> Charter: http://lists.netsys.com/full-disclosure-charter.html