Category Archives: linux

Shellcode: Dual Mode (x86 + x86-64) Linux shellcode

Introduction Someone asked me recently what do you mean by “dual mode shellcode”? and it seems the wording is slightly ambiguous to those unfamiliar with the different operating modes of a CPU like x86 so I just wanted to clarify … Continue reading

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Basic shells for Linux and BSD

Introduction Here are 4 examples of how to spawn a shell on Linux, BSD and Mac OSX for the purpose of accepting commands and sending the output over TCP. I do not use TTY or PTY shells here for this … Continue reading

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Shellcode: Execute command for x32/x64 Linux / Windows / BSD

Introduction I was hoping to present here a code that would execute perfectly on 32/64-bit Linux/BSD and Windows systems derived from code discussed here The 64-bit code will execute on all 3 systems but not 32-bit versions of BSD because … Continue reading

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Shellcode: Detection between Windows/Linux/BSD on x86 architecture

Introduction While writing simple Linux/BSD shellcodes, I had a quick look through a FreeBSD/Linux bind shell written in 2002 by a talented coder who went by the pseudonym Z0MBiE. Some of you will know he wrote a lot of cool … Continue reading

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Shellcode: Linux x86-x64

Introduction Just a quick blog about some simple shellcodes for x64 build of Linux you might find useful as a reference if nothing else. 😉 Assemble as binary files with NASM/YASM and edit before execution. For example: yasm -fbin rs.asm … Continue reading

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Shellcodes: Executing Windows and Linux Shellcodes

Introduction Recently, I finished an interactive shell for windows written in C which is also position independent. The server component runs on UNIX based OS and I was trying to test out delivery of the PIC to windows machine over … Continue reading

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