Tag Archives: assembly

Shellcode: In-Memory Execution of JavaScript, VBScript, JScript and XSL

Introduction UPDATE: After being available for twenty years, Dr.Dobb’s removed access to two articles linked from here. I’ve no idea why. A DynaCall() Function for Win32 was published in the August 1998 edition of Dr.Dobbs Journal. The author, Ton Plooy, … Continue reading

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Shellcode: Using the Exception Directory to find GetProcAddress

Introduction Let’s say you want the location of the GetProcAddress API in memory, but you can’t use the Import Address Table (IAT) or the Export Address Table (EAT). What other ways can you do it?. Perhaps there are many ways, … Continue reading

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A Guide to ARM64 / AArch64 Assembly on Linux with Shellcodes and Cryptography

Introduction The Cortex-A76 codenamed “Enyo” will be the first of three CPU cores from ARM designed to target the laptop market between 2018-2020. ARM already has a monopoly on handheld devices, and are now projected to take a share of … Continue reading

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Shellcode: Synchronous shell for Linux in amd64 assembly

Introduction Some weeks ago, I posted a synchronous shell in assembly for Linux/x86, and here’s the implementation for Linux/amd64. I will post one for Linux/ARM32 later, but then what? Is that the end? The purpose of the synchronous shell is … Continue reading

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Shellcode: Linux ARM Thumb mode

Introduction Just a quick post about some shellcodes for a raspberry pi 3 I purchased recently to learn ARM assembly. For those interested in developing your own, you can find a full list of Linux system calls in Thumb mode … Continue reading

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Shellcode: x86 optimizations part 1

Introduction What follows are a number of basic ways to compact shellcodes. In a follow up post, I’ll discuss a few ways to obfuscate them which might be useful for evading signature detection algorithms. Some of the examples illustrated here … Continue reading

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Shellcode: Resolving API addresses in memory

Introduction A basic but core function of all Position Independent Code (PIC) for windows is to resolve the address of API functions at runtime. It’s an important task with a number of options available. Here, we’ll examine 2 popular methods … Continue reading

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