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_cih_
Joined: Wed Sep 13, 2006 5:50 pm Posts: 10
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Posted: Fri Jan 05, 2007 1:36 am Post subject: Question about linux shellcode |
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Hello everybody,
I am trying to write a simple shellcode, but I am having some difficulties.
i.e
I have following codes ( with following hex represenation respectively ) :
..
jmp 0x8048243<main+91> (e9 3a 00 00 00)
..
mov $0x9ed, %ecx (b9 ed 09 00 00)
..
js 0x804824f<main+103> (78 00)
..
As you can see the problem I have are the 00-s in the shellcode.If i want to overflow a character buffer, such null bytes will be considered as end of string. Can anybody hint me on any workaround on one of the samples above ?
Thanks. |
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Steogede LXF regular
Joined: Thu May 04, 2006 6:39 pm Posts: 145
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Posted: Tue Jan 16, 2007 10:13 am Post subject: Re: Question about linux shellcode |
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| _cih_ wrote: | Hello everybody,
I am trying to write a simple shellcode, but I am having some difficulties.
i.e
I have following codes ( with following hex represenation respectively ) :
..
jmp 0x8048243<main+91> (e9 3a 00 00 00)
..
mov $0x9ed, %ecx (b9 ed 09 00 00)
..
js 0x804824f<main+103> (78 00)
..
As you can see the problem I have are the 00-s in the shellcode.If i want to overflow a character buffer, such null bytes will be considered as end of string. Can anybody hint me on any workaround on one of the samples above ?
Thanks. |
You have a shell that understands Assembly? Perhaps it would help if you mentioned which shell you are using, it certainly isn't BASH. |
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jjmac LXF regular
Joined: Fri Apr 08, 2005 2:32 am Posts: 1996 Location: Sydney, Australia
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Posted: Tue Jan 16, 2007 10:26 am Post subject: RE: Re: Question about linux shellcode |
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>>
If i want to overflow a character buffer
>>
Why would you want to do that ?
jm _________________ http://counter.li.org
#313537
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